What ever floats their boat.
I fired one round out of a single shot .50 BMG wearing foam ear plugs and ear muffs. Decided that was enough. I didn't get hurt, and my ears stopped ringing in a bout an hour, but I sure as little green apples didn't want to do it again. That rifle is about useless.
I've also fired an 8.5 lb (including scope) .338 Lapua, with a muzzle brake, pushing a max load behind a .300SMK. I could deal with that for 5 or six shots on the bench, a few more standing. But I'm glad I don't have to hunt with one. It was loud but not nearly as loud as the .50. Foam plus muffs was almost enough.
I like my .30-06 and 7mm Rem Mag. If it's too big to kill with them, I'm not going to hunt it.
Fitch