The Signature rings are a very good idea, but when I tighten them, the caps don't seem to be straight (the top ring half seems to have more gap fore or aft and are not straight to the bottom). I guess they slide a little on the plastic insert and there's only one screw on each side to tighten. I think this problem for me would be solved if there were 4 screws to hold the tops on instead of just 2.
When installing the ring caps, I've found that snugging down the screws by alternating side to side, while holding the cap centered, should prevent this. I'm also careful to insure that the gaps between the cap and bottom half is roughly equal on each side. And I resist the temptation to torque the hell out of the screws as the plastic bearings crush around the scope tube.
I've yet to have a scope slip due to recoil, including on my 300 WM. I think the inserts actually improve grip.
