I'll have to agree with DoubleD here.

When I was in gunsmithing school we tried many different brakes and most of them work very well. Especially on overbore cartridges. The only thing we couldn't do at school was come up with a quiet brake. THERE ARE NONE! I don't care what you have read in advertisements, If they tell you it's quiet because it's got fancy angled holes away from the shooter it's BS. Don't waste your money. The angled holes make them less effective as a brake than the ones that have holes at 90 deg from the bore. The cheap ones work as well as any providing the bullet doesn't hit the brake on the way down range. The larger in diameter the more effective they are.

I've heard rumors about Magna ported barrels coming apart but never seen any myself. If you think about it from an engineering standpoint, you are creating a weak point on one side of the barrel. Again I've never seen this first hand.

DD says everyone needs a heavy varmint gun with a brake, and he's right. Even a light weight varmint blaster with a brake provides the shooter with a great view of terminal ballistics. Just don't forget to wear earplugs and ear muffs. I built a 22-250 improved with a brake and the rifle doesn't move when you pull the trigger. It does however blast most of the paint off the hood on my GMC and seriously sand blast the windshield.

gunmaker
http://users.elknet.net/chico