I don't currently own one anymore but did have brief opportunities to use it. It is good, solid and in my opinion, better than the cheap aluminum receiver mounts available in the $50-150 price range.
It only fits single slot optical sights though. Generally, it only fits chinese barrels, but your mileage may vary(for success on a US barrel).
Bottom line: Best cheap mount since the Rooster mount.
If you are looking for a more versatile(for different optics, ie scopes), Ultimak is the key player and balance between weight and being a solid mount for any optic.