Any would work naturally. A .338,.358, .375 of whatever ilk is going to be more adept at "all around" type of work Than the larger bores. I have a .338 Win. and a .375 H&H. And even though I am a handloader I am pretty sure "in the event" you had an ammo problem you can find flavors of either caliber all over the world. Perhaps the Ruger rounds will have that availibility in the future, who knows.

So if I had to choose, since I have a .338 and .375 and they both are pretty similiar in size and weight I will pick the .375. It just works and is still a benchmark.