All I can say is WOW!!!  I ordered the upper from John Holliger (his special RRA upgrade) and a complete NM lower. The fit is TIGHT!! Tighter than...well, let's just say it's tight.  Mr. Holliger did an amazing job on the RRA trigger.  Range report will come next week.  
Also, I'd like to HIGHLY recommend Mr. Patrick Stanley of Kentucky Shooting Sports at kyarms.com.  He's on the USMC res. highpower team and is a true gentleman.  He politely dealt with all of my questions (and there were a lot)and has GREAT prices!!!  I don't know how to get someone added to the list of vendors, but I'd like to see him there.  A truly great man to deal with.
later
R

Trumpet, post a pic man!!!
Does John Holliger have a website or anything like that? I'm curious now, I've never heard of him or what he does.

i just shot my RRA NM lower with a bushy upper for the first time monday. very nice.

Check out info about John on the competition board.  His name's all over the place there.  As far as pics, I don't have the ability, but just look at the Rock River DCM rifle.  It's pretty much the same thing except John builds the upper from scratch with the RRA parts.  Plus he pinned the sights etc.  What really sold me on RRA is the fact that I purchased the upper and lower seperately, yet the fit is phenomenal!
Later,
R