Just got my remington 700 police in 300 win mag back from Vais arms inc. with muzzle brake and trigger job. Can't wait to shoot it. They claim 50% less felt recoil and only a couple decibels louder.
They work well. I have muzzle breaks on a 300WSM, a 7MM Mag, and a Rem 260. You will see 40% to 50% in recoil reduction. and most guns shoot better with a break on them. Best part is you can just unscrew it, take it off if you want and screw on a trread protector. That way you can shhoot it with or without the break.