I used my Reflex II w/12.5 moa triangle (on a 16" gun) at a tactical shoot that features pop-up man sized targets from 25 to 500 meters.
The Reflex II is easy to use out to about 300 meters, and it's just tough to see those guys in the grass past that. Still, I get hits all the way out to 500.
I would highly recommend this sight. For CQB work, it's a near perfect sight.