Repeated exsposure at these high decibles only takes a short time period for permanant damage to occur.
I wear hearing portection shooting and hunting in any situation.
Daveosok makes a good point, and a good suggestion too. I'm guilty of not using any in the field when it's a shoot fast type deal, as I'm sure many do as well. It's important to understand that it has a cumulative effect though, and every time you don;t have protection on, it does cause more hearing loss.
I worked with an older gentleman who drove truck too, his hearing was real, real bad. If he was walking away from you, and you tried to get his attention, you'd better hollar, cause he'd never hear you unless you did, and a lot of times you had to hollar to him even louder.
Even talking to him face to face you had to talk super loud. He refused to wear hearing aids, which he was supposed to by law when he was on the road or on a fork lift. Jim's one of the nicest guys you'd ever meet, and it was sad to see the difficulties he had becuase of his hearing, it makes me think of mine every day. He's still a hell of a hunter, but he does it all by sight... this is a fact.
I like the design of the Holland Quick Discharge Brake, especially if you use a bipod like I do. It's very effective too.
I do believe it's a bit easier for most anyone to shoot a rifle more accurately with a brake on it. Some people have a very difficult time fighting a natural reaction to recoil, same with muzzle blast. It's far easier to deal with working up to heavy recoil gradually, smaller cartridges and muzzle brakes help immencely until you get the mind over matter sorta thing worked out.
I'd go with a threaded on type for sure. If you can manage the recoil without one and you hunt up close without hearing protection at times, this is a big plus!
Ha! I have a 454 Casull, ported, and I refuse to fire it without protection unless I'm being charged by a friggin BB... PERIOD! Makes ya feel like your ears is friggin bleeeeedin!!