I installed my RAS today as well. Attempted to mount my Reflex II forward for greater eye relief. I noticed I was off center on the post. I got to looking and low and behold the picatinny on the RAS is narrower than the BM. I got to looking at the trijicon mount (high) and it is correct for the flat-top. The RAS rail is too narrow, not the BM flat-top rail. It is also a curley hair higher IMHO. I didn't mind that so much since it give a clearer (unobstructed) view. And I can co-witness the sights. I still like the RAS, but it is a concern, and I'm some what bummed since I could have easily bought a Fobus handguard set and had the same functionality as the RAS, but about $230 cheaper, IMHO.