Ever slide around in your seats?

[joshd2012]

Well, I may have found a problem. And no, I am not affiliated with this company, but I think their product may work.

Anyway, I hate when I slide around in the seat when going around a corner. I usually grab the edge of the seat so I don't get pushed against the door. But these guys may have found a solution to racing seat belts:

http://www.cg-lock.com/home.htm

Its basically a metal piece which keeps the lap belt snug while allowing the shoulder belt to move freely. Has anyone tried this product. A racer who mods on another board sells these, and his friend developed them. I hadn't heard of them until tonight, so I was wondering if anyone had any experience with them or not?