06, because 06. And 375 H&H wasn't on the list...
The 7x57 is an excellent cartridge, surpassed by the 7mm-08 in a true short action. I like the 7x57 just fine, but it wouldn't be my first choice of 7mm.I feel sorry for the poor 7x57 Mauser. Not a single vote so far. It’s kind of a textbook case of a nearly perfect round, but hampered severely by lack of rifles chambered in it, and lack of good factory ammo choices.