I am a big fan of Aimpoint red dot optics, specifically the T2. I use that model almost exclusively on my ARs and it works well, but I have noticed certain problems with it. For one, the red "dot" is not a dot. In my scopes it is usually a diagonal slash, albeit a short slash. Typically that isn't a problem, except for under magnification. Another factor has been the fact that the scopes are advertised as parallax-free. I knew that wasn't true, but assumed that the amount of parallax was negligible. I never tested how much parallax there is, but someone else did.
Eric Dorenbush, owner of Green Eye Tactical, did a test on a variety of optics. Here is what he found. He has already told me this is public information and can be shared.
https://www.dropbox.com/s/5zgsq2kq6jri8bd/Red%20Dot%20Test%20Report%20.pdf?dl=0
