Also look at the Aimpoint H1Micro. Advantage of the Aimpoint is up to 50,000hrs battery life, is parallax free to infinity. Once zeroed the dot can be anywhere in the field of view and if it is on target you are on target. That is if you eye is not precisely placed to have dot in the centre of the scope it does not mater.

The problem I have experienced with the M111 type is that I have to go hunting with eye placement to find the reticle/dot. This weakness may well have been overcome as it is years since I tried one of these holographic sights.