Thanks for an excellent review - I had the same selection problems and ended up with three AR's:
AR 1 - ACOG 3x (TA33-8) with an RMR 08 on a 45 degree rollover.
That AR is real nice but by the time I got everything on (flashlight, laser, etc.) it the rifle weighed 8.5 lbs so it was time to build a "light" AR
AR 2 - Trijicon RM 04 as primary sight on a high TA34 mount - with flip up peep as a backup. Although the dual power RMR can be a little faint under some lighting conditions this setup works because the dot will sit over the front sight post with little effort making it visible even under the worst of conditions (RMR's have an issue with sighting from a dark room to something outside such as bright sun lit building walls or sky) The only thing bad about the nearly indestructible RMR as a primary sight is the fact that a raindrop in the wrong spot will mess up the sight picture.
AR 3 - Now that I had two real nice AR's I found that my popularity had increased and buddies wanted to "try them out" Since I'm a little anal about them, but still wanted to keep friends I realized that I needed a third AR. This one has an Aimpoint Patrol and 45 degree mounted iron sights. I could have put standard flip ups but I had a 45 degree set lying around, so why not!
In my life the most dangerous thing I do is my drive to work on the freeway so these are just toys got out of control, but I did learn two things from this:
Thing I learned # 1 - The RMRs are well made and easy to adjust but in the process of setting my rifles up I actually got three of them. An RMR08A (amber triangle) was noticeably worse at gathering ambient light than were the other two. In a completely dark room they all worked the same on trijicon only, but in the "dark to light" scenario mentioned above the RMR 08 was not functional while the other two, identical sights, were. The RMR 08 is now back at Trijicon. Without the other two as a reference I never would have noticed the problem.
Thing I learned #2 - At up to 100 yards (and possibly greater distances) the dot sights are much superior to iron sights for target acquisition and at least equal for accuracy.