Here is an example of fixed rings (Burris Tact) which you can see the lack of adjustablity with the set up.
Where the cantilever mount allows a lot of positioning freedom. These happen to be Armalite mounts but basically the same as the Burris mount (except for US made I think). The Burris mount is a good one despite its origin.
This is the Burris DMS (?) scope which is not great for coyotes as too much play in the circle aiming point vs crosshairs, but would work great for other things.