I originally mounted a VXL 50mm on the one piece rail, but was alittle too high to take advantage of having the L shape. Just recently placed a 6.5-20 mark 4 on it and the rail does have about 15 to 20 MOA built in. Not sure if its worth the money it you put a normal 3-9 scope on it, but I plan on trying to shoot longer ranges. Nice piece of steel.
Pros: Easily mounted without any trouble.
Cons: None that I can see at this time.
This review was written in the old system and had content requirements that are different than reviews written today.