I bought this magnifier to use with my Aimpoint PRO on my Colt 6940. I did not see the point of spending $500 + on the Aimpoint magnifier. I already have an older version of the Vortex magnifier used in combination with the Vortex Sparq on my S&W M&P 15. This new Vortex magnifier is an improvement. The mount is better, and it is easier to center the red dot in the view. This magnifier works great with the Aimpoint, with the additional shim provided. I would recommend this. I also have an Eotech paired with the Eotech magnifier on a Colt 6920 (I have several AR's). I don't think the Eotech magnifier is any better.
Pros: Quality optic, low cost, easy to use flip mount
Cons: Eye relief
This review was written in the old system and had content requirements that are different than reviews written today.