I have a muzzle brake on my Remington Sendero SF in .300 Win. Mag. The gun does kick less than a 270, but I wouldn't say that it kicks like a .243. BTW, you should ALWAYS wear hearing protection at the shooting range, especially when you shoot a gun with a muzzle brake, and it would be a good idea to use hearing protection when hunting with it too.
As for hogs, they are tough critters and I understand your wanting, or thinking that you want, a .300 Win. Mag. But believe me, you would be better off with a .30-06 with stout 180 grain bullets like Barnes X. I use a PMC 165 Barnes X in my .30-06 and have killed quite a few hogs with it (not to mention quite a few deer with it too.) It is the perfect combo deer/hog gun in my opinion.