I hate to say it guys, but I prefer A2 uppers.  I have a couple of A3s (a 16" M4 and an 11.5" HBAR) all decked out (both have ARMS SIR 45 rigs and ARMS throw-lever mounts).  But with my size (I am 6'7") I hate dropping my head over to get a decent view at the optics.  On an A2 with an ARMS #2 base I barely have to move my head and I can get a perfect view at the glass.  I know that there are issues with mounting the optics that high, but it is just more comfortable for me to shoot that way.  Also, just for reference, most of my shooting now is at less than 100 yards.  Got the reg. Lightning Link and Scott Bell trigger pack in and I am running auto almost all the time.  Anybody else out there like me?

Well, I prefer the flat top, but it seems you have found a system that works for you.

How is your cheek weld with that set up?  What is it like shooting prone?

Fragile A2 rear sight?? I have seen a few that dumb privates ajusted the Elevation all the way up and played in the sand and jammed in the up position but other than that I have never seen a broken A2 rear sight.  The windage and elevation will not ajust itself you have to do that for it.

Make mine a flattop (I'm only 6ft 2in tall).