I have a 30-06 and my buddy has a .270 and we have both shot mulies equally dead.
Since the magnums are even more powerful, I suspect they will do just as well as our cartridges over longer distances.
I'd try to find a rifle that works for you (easy to carry, quick to shoulder, easy to aim, recoil doesn't kill you, etc) and then decide.
If you spend most of your practice time firing a .22 to save ammo, the ammo cost doesn't become a major factor.
Good luck this year and ongoing!
I'm right about the metric system 3/4 of the time.