I just put an order in for a few parts from Cylinder and Slide, of which they state they have already been smoothed out and refined and simply just drop in the frame. I figured I would give them a try after hearing about how good a company they are from some friends of mine. What real refining goes into a GI model  or any mass production 1911 anyway? I can't see the companies out there investing too much time in a mass produced pistol,although I could be wrong,(of course I don't mean any custom shop guns or specialty pistols). Anyone have any thoughts on these parts or have you tried them? I know it is always better to have a smith do the work and have it custom done,but I would like to give their product a try,thanks.

I put their hammer & sear in a SA Bi-tone LW 5" .45 ACP after changing the guts of the ILS in the MSH.  I was very pleased.

Good shooting!

Are you talking about the fire control parts set?  I have one in my Kimber.  I can't remember which one.  Dropped right in like they said and works just fine.  I have around 3k rounds with that kit in and no problems.

It is one of the kits. I went to a gunsmith who started rattling off a list of parts needed for the pistol and it was more expensive with  cheaper parts from him and it didn't even look like he cared about doing it at all,(along with an attitude), so I figured I would just replace the parts myself and see how it does. If there are any problems, I will find another smith.

C&S fire control parts are the best available in my opinion.  I've got 3 different kits, and all were basically drop in parts.  I had to tweak the thumb safety on one pistol to fit the sear correctly, but that was the only issue.  I wouldn't buy anybody elses kit at this time.

Recently I have purchased C&S's SFS System as well as their Ultralight Hammer and matching sear.
i couldn't have been happier with their CS. Replies to emails, etc were ASAP. Ordering support and help was very nice & well, helpfull.
I love the Ultralight hammer. That being said, the sear that came with it left a little to be desired.  The through hole was extremely tight. I've bought countless sears from God only knows how many different mfgrs and never had one this tight but I do realize parts slip through.  This one needs to be really opened up in order to work at all. To be honest I couldn't even get an idea if it was cut correctly since it wouldn't rotate about the pin correctly.   The good news was that I got the part from Brownells and they have a no BS return policy and with my dealer discount it didn't hurt too much in the pocketbook.  Also, the hammer wound up working perfectly with another sear I had ordered from a different mfgr.  The Hammer and sear setup wound up working great. With the remainder of Trigger and sear spring parts I had utilized I got the trigger release I wanted.  I've wound up using Clarks sear spirngs in all my 1911's and love them.
Unfortunately, Brownells doesn't sell the drop in kits that C&S Sells directly & C&S doesn't or at least won't give me any kind of discount so I won't pay the asking price for the kit.  IMO I can buy the parts seperately and still pay less. Don't ask, I can...

As for the SFS System, I'm still on the fence on it. C&S doesn't make it. It is made in Belgium I believe, I'd have to pull the box out and look at it again to be sure. I cannot remember the companies name offhand.  RDHS I believe? Something like that....
It does drop right in, very easily. No adjustments or assembly of parts are needed.  Thank God because that Hammer looks like it could be a bear to assemble...
One key element that I still have yet to see in the description kind of honked me off and that is that the right side safety lever is made out of plastic. For approx $180 you'd think the levers could both have been made out of steel...  
Also, when the hammer is pressed forward, the safety levers are supposed to pop up/engage.  The safety levers on my unit DO NOT pop up/engage very high nor with very much authority.  
When the safety levers are pressed down to make ready to fire the levers will not move very far out of the way. Well, they will but they are under a spring tension so as soon as you release your thumb pressure the slightest bit the levers will rise back up leaving the left side lever riding just below the slide... And I do mean just below the slide... I cannot wait to see how this thumb safety lever looks after a hundred rounds.
The whole kit comes with a Slide Lock Lever/Pin but unless you're into the long extended type levers/pins you won't want to use it. Mines just sitting int the box.  You'd need to seriously modify your left side grip in order to use it.  At least I would mine...  I'd have been happier if they would have included the ambi mag release button the mfgr makes instead...
I'd still easily recommend C&S on so many of their parts alone.  The fit and finish is great.  My grips on this kit cannot simply be attributed to them. After all they don't make this SFS System. They just sell it here in the US.
Go ahead and buy from them with confidence... They make some pretty good products...

Quoted: It is one of the kits. I went to a gunsmith who started rattling off a list of parts needed for the pistol and it was more expensive with  cheaper parts from him and it didn't even look like he cared about doing it at all,(along with an attitude), so I figured I would just replace the parts myself and see how it does. If there are any problems, I will find another smith.

I know who you visited and it doesn't surprise me one bit.

I bought a 5lb FCG (disconnector, sear, sear spring, Hammer, MHS) from them.  Dropped right in.  Had to fit the thumb safety that is normal to have to do.  It's actually really easy to do.