I can tell you a bit about the quick release rings/bases. In my experience, they return to zero when removed and remounted on the same barrel. They need to be resighted, however, when you move them from barrel to barrel due to minor misalignment differences, recoil changes, etc. They do allow you to use one scope on different barrels, but it is a sufficiently large inconvenience that I gave up and just bought enough scopes to go around. Hope this helps you.
RonF