Yes, they do.
Personally, I've never been a fan of bsquares for 2 reasons.
1. You can't lock down the screws on them because they will compress the walls of your receiver and prevent your action from properly functioning. There is always the chance for slight play because of this. The idea of having a mount secured to the top of the receiver just seems like a better, more durable and rigid platform.
2. Cosmetically, I think they look cumbersome and they scratch the finish of your gun when putting them on and taking them off.
Just my 2 cents. Best of luck with whatever you decide.