The only thing I don't like about them is that it takes some trial and error effort to align the levers so that they look nice after they are tightened. However, once tightened, they stay tight.
The Leupold quick detach rings are designed so that you can adjust the angle of the levers after they are tightened. I use the Leupolds on the Weaver base of a target pistol with great satisfaction, but I have never tried it on a rifle.