Jason,
No idea. I've got older Talley Ltwt's on ULA's with the hex screws instead of Torx, and I haven't had any problems. I've had good luck with all of them, but I'm careful about NOT over-tightening my screws. Not saying the rings are not at fault......but I've never had a failure. I'd guess that I've used 30 or so sets over the years.
