Between the two, I'd choose the 2-7x. Have it mounted as low as possible. It will be plenty of scope for hunting anything you'll be hunting with a muzzle loader.
I'd go with the higher power myself. I've used a 50mm for many years with no issues. If you have an issue with getting down on the stock, its easy to fix with items you already have at home. You can't hit what you can't see.
Definately the Elite! 2-7x32mm power is all you need. I have that sane scope on a rifle. Amazing light gathering ability, solid made, and just a nice scope in the woods.