Quoted:
I think you have a pretty nice build list there.

I have to admit that it is news to me that the other Raptor charging handles do not have equal length levers.  I can not say that I have ever noticed that on my Noveske branded Raptor and I certainly wouldn't let that steer you away from the Raptor if you can not get your hands on the UC version.

I also have a raptor, and while I think its a great charging handle, it does bother me that the left handle is shorter than the right... I charge my gun with my left hand often and I do notice it.  The UC seems like the perfect fix to what should have never been a problem to begin with (for me at least) I have no idea why they made the left handle smaller.

My thoughts on the rest of your list are as follows:

Geissele makes a hell of a trigger.  I have an SD-C and love it.  My last trigger purchase was a Wilson Combat TR-TTU and that thing made everyone who shot it nervous.  Even though it is rated at a 4lb pull, I can tell you that a 4lb single vs a 4.5lb 2stage are worlds apart in feel.  I sold the Wilson and will now stick with 2 stage Geissele's going forward.  So before you decide on the SD3G I would test one out for yourself.  You might be surprised how light it is.

I currently have a SSA-E and a LaRue MTB on my lowers.  I have not tried a light single stage before so this is a good suggestion.  I recently learned that V-Tac actually made a version of the SD3G with a heavy spring... they must have gotten scared also! (kidding)

I see only 1 V7 part on your list.  I understand that they are spendy but I always say "buy once, cry once".  Not that mil-spec parts aren't more than adequate but the V7 stuff is just so nice that it seems a crime not to use as mush of it as you can afford, especially considering this looks to be a high end build.

The more I think about it, yes I will use more V7 and or BAD parts in the lower. I have never been much of a fancy lower kinda guy, alway buying something simple and forged.  This build is of course a total 180 from that mentality so I am learning to embrace the fact that I am gonna end up with a $l,000 lower.  In truth its a bit of a vanity project so what the hell.

The K2 isn't a bad choice for an upright grip but I would also consider the BCM and HK battle grip too.  I chose the HK V2 MR556 grip and it is my favorite upright style grip.  The K2 & BCM both have storage compartments though if you need that.  I didn't.

I need to get to a shop and try out some grips.  My other builds are more long range oriented so I have used different type of grips.  I am also interesed in the ones you mentioned and B5 as well as Umbrella Corps.

I have no experience with the Seekins AGB but the Syrac has been great for me and I also hear good things about the one SLR makes so just two more considerations there.

Another one I thought about aside from the 2 mentioned is Oden.  From what I have read they all work just fine.  This decision is based on price.  The MSRP of the seekins is a bit lower, Oden is next than Syrac and SLR.  If I can find one on the EE I will surly snatch it up.

I have never seen that SI Megafin rail before but I have to admit that it looks pretty cool.  It does seem a little on the heavy side but It does look handsome.  If you decide to use it let me know your impressions.  The one thing I would mention about it though is that the MBUS will look really bulky compared to that tiny front sight.  Maybe look at the Spikes Micro Sight or the one by KAC to better match the profile of the front (though nothing really will).

Good call re the sights. I checked out the Spikes Micro and KAC, The KACs could be good, but the best fit I think it the Bobro Lowrider, I just need to find someone who wants a front sight as they are only sold in pairs....IM me if you want to split a pair of Bobro Lowriders LINK  Regarding the weight, with the barrel nut its about 14.5 oz... this is pretty light I think.  Maybe closer in weight to rails that are a little longer but the rail is sorta thick (fits suppressor underneath HG) so I think it can still be called a LW HG

Most of my AR barrel experience is with Noveske and you can't go wrong with them but I have also shot a few WIlson Combat's and have really been impressed with them for the price and appearance.

I do not have experience with the King Comp but IMO that thing is ugly.  If you need a comp then Battlecomp is the way to go.  Otherwise a nice 3 prong flash hider always looks tits and does the job.

I decided to go with the King Comp because its made by Strike and is threaded to accept the Ferfrans CRD, which I already own.  If your not familiar with the CRD its a "Concussion Reduction Device" looks like a little can that goes over your brake to push the pressure from the brake forward.  I like it alot because the Ferfrans brake is LOUD, and has serious concussion.  More than any other brake I have tried.  Its even louder than the Surfire SOCOM to give you reference. I coud use the Ferfrans brake that is currently on another rifle, the king comp, or Strike makes 2 other devices that work with the CRD and another one is on the way.  So I am not married to the king comp.

I just don't know about that CMT receiver stock thing.  I like the concept but I am not so sure about the execution.  The cheek piece should be attached to the back of the lower like a UBR so that you can shoot NTCH.  It is also just 2" shorter collapsed than a carbine buffer tube and since you are going with a 10" hand guard and a longer style muzzle device I don't know that the 2" will really matter that much.  I do think it has a neat look to it but I don't think I want to be a $650 guinea pig to see how practical/comfortable it is to shoot.

So the upper is already purchased.  I am married to it. I gave the points mentioned above a lot of consideration.  I could go on and on about my thought process but what sealed the deal was I got a guarantee.  If I dont like it, for any reason, money back no questions asked. That did it for me.

The last thing I have to add is that you can not go wrong with a JP LMOS carrier.  Mine has been fantastic paired with my AGB.  If I were buying today I probably would have gone with the JP aluminum one or the Boomfab tit carrier but neither were out yet when I made my last BCG purchase.  I do not regret the purchase though and because mine in steel it can probably take more of a beating than the other 2 I mentioned.

I just cant justify spending that kinda coin on a BCG.  Maybe the JP steel versions around 220, I could do but spending 400-500 on a BCG or just a carrier I cant bring myself to do.  I have three carriers right now, one is from SSA cost me 88 bucks for the entire BCG, other one is a fail zero, third is a Sprikes NIB.  Honestly they all run in different rifles so I have not done much of a scientific comparison but they all work equally fine.  the plated ones (fail zero and Spikes) are a little easier to clean but as far as my experience goes that is the only difference.  I just dont see the value add of a $400-$600 BCG.  Aside from saving some weight and increased reliability why go with such a high end BCG?  I shoot at paper, steel and prairie dogs.  If my gun jams, it sucks but its always been my fault for letting it get so dirty and the end result is me shouting a curse word and yanking the CH.  I dont compete and wont be in a gunfight any time soon so I cant reason spending cash like that on a BCG.  Any one with reasons that support the hight end BCGs let me know.

Be sure to post some pics when you get this thing together.  It sounds like a great build.

Quoted:
I think you have a pretty nice build list there.

I have to admit that it is news to me that the other Raptor charging handles do not have equal length levers.  I can not say that I have ever noticed that on my Noveske branded Raptor and I certainly wouldn't let that steer you away from the Raptor if you can not get your hands on the UC version.

I also have a raptor, and while I think its a great charging handle, it does bother me that the left handle is shorter than the right... I charge my gun with my left hand often and I do notice it.  The UC seems like the perfect fix to what should have never been a problem to begin with (for me at least) I have no idea why they made the left handle smaller.

I never noticed that they are not the same length.  If they are different then it must be a very minor difference in length.

My thoughts on the rest of your list are as follows:

Geissele makes a hell of a trigger.  I have an SD-C and love it.  My last trigger purchase was a Wilson Combat TR-TTU and that thing made everyone who shot it nervous.  Even though it is rated at a 4lb pull, I can tell you that a 4lb single vs a 4.5lb 2stage are worlds apart in feel.  I sold the Wilson and will now stick with 2 stage Geissele's going forward.  So before you decide on the SD3G I would test one out for yourself.  You might be surprised how light it is.

I currently have a SSA-E and a LaRue MTB on my lowers.  I have not tried a light single stage before so this is a good suggestion.  I recently learned that V-Tac actually made a version of the SD3G with a heavy spring... they must have gotten scared also! (kidding)

I see only 1 V7 part on your list.  I understand that they are spendy but I always say "buy once, cry once".  Not that mil-spec parts aren't more than adequate but the V7 stuff is just so nice that it seems a crime not to use as mush of it as you can afford, especially considering this looks to be a high end build.

The more I think about it, yes I will use more V7 and or BAD parts in the lower. I have never been much of a fancy lower kinda guy, alway buying something simple and forged.  This build is of course a total 180 from that mentality so I am learning to embrace the fact that I am gonna end up with a $l,000 lower.  In truth its a bit of a vanity project so what the hell.

The K2 isn't a bad choice for an upright grip but I would also consider the BCM and HK battle grip too.  I chose the HK V2 MR556 grip and it is my favorite upright style grip.  The K2 & BCM both have storage compartments though if you need that.  I didn't.

I need to get to a shop and try out some grips.  My other builds are more long range oriented so I have used different type of grips.  I am also interesed in the ones you mentioned and B5 as well as Umbrella Corps.

I forgot to mention the Grip 23.  I have not tried that one yet but a stippled one would be nice and I will probably try one in the near future.

I have no experience with the Seekins AGB but the Syrac has been great for me and I also hear good things about the one SLR makes so just two more considerations there.

Another one I thought about aside from the 2 mentioned is Oden.  From what I have read they all work just fine.  This decision is based on price.  The MSRP of the seekins is a bit lower, Oden is next than Syrac and SLR.  If I can find one on the EE I will surly snatch it up.

I have never seen that SI Megafin rail before but I have to admit that it looks pretty cool.  It does seem a little on the heavy side but It does look handsome.  If you decide to use it let me know your impressions.  The one thing I would mention about it though is that the MBUS will look really bulky compared to that tiny front sight.  Maybe look at the Spikes Micro Sight or the one by KAC to better match the profile of the front (though nothing really will).

Good call re the sights. I checked out the Spikes Micro and KAC, The KACs could be good, but the best fit I think it the Bobro Lowrider, I just need to find someone who wants a front sight as they are only sold in pairs....IM me if you want to split a pair of Bobro Lowriders LINK  Regarding the weight, with the barrel nut its about 14.5 oz... this is pretty light I think.  Maybe closer in weight to rails that are a little longer but the rail is sorta thick (fits suppressor underneath HG) so I think it can still be called a LW HG

Good luck finding someone to separate a set of Bobro's.  Finding them in stock has been a chore since they were released.

Report back with pictures on your impression of the SI rail quality, it interests me.

Most of my AR barrel experience is with Noveske and you can't go wrong with them but I have also shot a few WIlson Combat's and have really been impressed with them for the price and appearance.

I do not have experience with the King Comp but IMO that thing is ugly.  If you need a comp then Battlecomp is the way to go.  Otherwise a nice 3 prong flash hider always looks tits and does the job.

I decided to go with the King Comp because its made by Strike and is threaded to accept the Ferfrans CRD, which I already own.  If your not familiar with the CRD its a "Concussion Reduction Device" looks like a little can that goes over your brake to push the pressure from the brake forward.  I like it alot because the Ferfrans brake is LOUD, and has serious concussion.  More than any other brake I have tried.  Its even louder than the Surfire SOCOM to give you reference. I coud use the Ferfrans brake that is currently on another rifle, the king comp, or Strike makes 2 other devices that work with the CRD and another one is on the way.  So I am not married to the king comp.

I just don't know about that CMT receiver stock thing.  I like the concept but I am not so sure about the execution.  The cheek piece should be attached to the back of the lower like a UBR so that you can shoot NTCH.  It is also just 2" shorter collapsed than a carbine buffer tube and since you are going with a 10" hand guard and a longer style muzzle device I don't know that the 2" will really matter that much.  I do think it has a neat look to it but I don't think I want to be a $650 guinea pig to see how practical/comfortable it is to shoot.

So the upper is already purchased.  I am married to it. I gave the points mentioned above a lot of consideration.  I could go on and on about my thought process but what sealed the deal was I got a guarantee.  If I dont like it, for any reason, money back no questions asked. That did it for me.

You can't beat a guarantee like that.

The last thing I have to add is that you can not go wrong with a JP LMOS carrier.  Mine has been fantastic paired with my AGB.  If I were buying today I probably would have gone with the JP aluminum one or the Boomfab tit carrier but neither were out yet when I made my last BCG purchase.  I do not regret the purchase though and because mine in steel it can probably take more of a beating than the other 2 I mentioned.

I just cant justify spending that kinda coin on a BCG.  Maybe the JP steel versions around 220, I could do but spending 400-500 on a BCG or just a carrier I cant bring myself to do.  I have three carriers right now, one is from SSA cost me 88 bucks for the entire BCG, other one is a fail zero, third is a Sprikes NIB.  Honestly they all run in different rifles so I have not done much of a scientific comparison but they all work equally fine.  the plated ones (fail zero and Spikes) are a little easier to clean but as far as my experience goes that is the only difference.  I just dont see the value add of a $400-$600 BCG.  Aside from saving some weight and increased reliability why go with such a high end BCG?  I shoot at paper, steel and prairie dogs.  If my gun jams, it sucks but its always been my fault for letting it get so dirty and the end result is me shouting a curse word and yanking the CH.  I dont compete and wont be in a gunfight any time soon so I cant reason spending cash like that on a BCG.  Any one with reasons that support the hight end BCGs let me know.

Be sure to post some pics when you get this thing together.  It sounds like a great build.