I have Vais brakes on 3 rifles and they are the only brake I've ever seen at the range that don't draw dirty looks from the folks on the next benches.

The key to the Vais brake is the fact the gas is in the brake longer and doesn't exit as fast because the gas from the internal chambers collides at 90 degrees effectively slowing it down....less velcoity coming out the holes equates to less noise and especially less blast back to the shooter. I agree they are marginally less effective than other brakes but what little you give up in recoil reduction is more than compensated for with a lot less blast.