Well, I took her shooting yesterday, and I really like the Holosight. I had no problems keeping everything on target once I had it sighted in. One hundred yards was the max I could shoot at, but with an M4 that is about right anyway. With it sighted in at 100 it shot high up close and personal. No problems with the Holosight at all, but did have a problem with my BUIS I put on. Actually, the problem must have been the gas block was crooked, as I had to crank the rear sight all the way left because the bullets were hitting so far right they were almost off the paper! I finally moved my gas block over some and got the rear sight where it is more centered and now everything is just hunky dory. This is a railed gas block and is held on by screws. Think I should lock-tite the screws? I would hate for the dang thing to come loose when I might actually need the gun!