IMHO with the exception of contender style handguns ,if you need a muzzlebreak for a rifleone should be shooting a less powerful round. For a person that is accomplished and spent the time learning how properly shoot powerful "magnum" rounds ,abovethe 300 mag ,there is no real advantage in quicker follow up shots. Personally I could be back on my target just as fast with my 375 H&H as my 308.
You'll find PH's in Africa that do no allow hunters to shoot rifles with muzzlebreaks and many a outfitter who cringes at the sight of one here.
I'd rather see a hunter that can place thier shots with percision and respect the limitations ofa caliber than choose a round that they need a muzzlebreak.