On the opening topic question. Having only shot one sambar stag, with a .30-06 and 180 gr Nosler Partition, for what its worth ... Have shot a good number of numerous other medium game with the .30 from various deer, donkeys, African game etc. The 7x57 is in the same general class as a .308, .30-06 and .270. As far as I am concerned the difference at the bleeding end with the right bullet and reasonable placement is not much.

I think a 7x57 with a suitable bullet, in the 160 to 175 gr range would make a really handy rifle for carrying in the Vic Alps for sambar and all sorts of other medium game elsewhere in the world.

A classic cartridge ideally suited to a handy carry rifle.

I think the guys that carry 9.3x62s, .375s and larger either want to use these for the sake of using them, want to carry that much more grunt and why not to make up for any error, or are carrying a larger calibre to make a difference for angling and rear end shots, running shots etc. The 9.3mm is one of the best choices for larger medium game so why not.

Finally, what would I carry? I would be happy to carry a 7x57. I would probably still prefer my .30-06, .308 or 9.3 mm. But almost certainly it would be the 8x68S next time.