one bad thing about vais is that it has holes all the way around, which on big guns, when you shoot prone, kicks up a lot of dust, dirt, or little rocks. can damage your nice 1000 dollar scope lens. you should wear hearing protection anyways when using any kind of brake. I used the type that had 3 holes on top, and the sides, for a total of 9 holes, it was a score hi version, i think its comparable to the qd holland type. i'll be getting the qd holland type on my 300 rum for my long range rifle. my current 300 rum has no brake, and I shoot it fine. but i live in a sandy environment where the vais is not the choice for where i live, and i prefer to shoot prone over any other position.