They are all well capable of any north american game. The .300 having the all around avantage but with more recoil. Do not buy that caliber in a light weight rifle and expect it to be enjoyable to shoot. The 7mm mag is in the same class almost in recoil.

As far as the 30-06 having a better bullet selection over the 300 win that is not so. Any bullet you can load in a 30-06 case you can load in a 300win case. Same bullet dia. .308 . The 300 Win mag factory ammo will cost you almost double the price of the 30-06.