I am looking to get a modular forearm for my RRA M4 and have narrowed it down to two products, the KAC RAS and RAS II.  

Aside from physical differences (e.g. the RAS II "hump"), how do the two differ?  Is the RAS II worth the extra money?  Does the "hump" get in the way?  Etc., etc.,...  

Any input from people who have either model would be great, especially why they bought the particular model they have.  Thanks for the help/suggestions.

I have a RAS II and I would definetly reccommend it. The hump is perfect for cowitnessing an Aimpoint for instance. Also you freefloat the barrel,and its torsionally stiffer so you can hang more bling off it if you want to without affecting anything.

I don't know what the price difference is these days but I say its worth the extra cash.

I have both so short and simple: The RAS 2 is around $30 more and worth it.  As mentioned above the RAS 2 free floats the barrel (BIG+) and mounts SOLID to the upper (BIG+).  While the top of the M4 RAS is fairly solid, due to the way the bottom rail mounts it leaves a little play side to side.  This is very noticeable when using a vertical grip, but it's not horrible.  As far as the "hump" being in the way, it really just depends on your sighting system.  A traditional scope + hump = problem.  An aimpoint or ACOG + hump = no problem.  Check with the dealers on the board or in the EE for good deals on both.

Ray

how about a 552??  i was curious if there's enough real estate to mount it in front of the "hump"??  ive seen the 551/511 (or whatever the ones with N batteries are called) mounted like this, but never the AA versions..

thanks


edited to make my post sound more like a question..


so is there room to mount a 552 in front of the hump??  from thelastgunslinger's post I'm pretty sure that it works, but i've got to get a straight answer before I'm positive..

thanks again

I use a 552 and got the RAS over the RASII for this reason.  I dont like having the sight all the way at the front of the rifle for a several reasons (balance, sight picture, etc.)  With the RAS, I have my 552 roughly centered over the delta ring, which is the perfect distance from my eye for me.  Also with it mounted there, it is still clamped to the flat top receiver, so I dont have to worry about the RAS not being quite as stable as a RASII or SIR for optics purposes.  Now I just need my dang Tango Down VFG!!

I have the RAS-II but not the Eotech, but it has been said in another topic that the Eotech will fit forward of the bridge and will fit on the flattop BUT you will not be able to mount a rear BUIS and the Eotech on the upper at the same time, no room for both.