Somewhere on the web is a write-up of compensators of various designs, how they work, how well they work, and if they (various brands) harm accuracy to any extent. It is quite a piece and it looked like the guy really did a lot of research and testing. I'll try to find...it has been a while. Bottom line of his write up was the J&P did the most for recoil reduction with the Vais(original design) coming very close second. He felt the Vais was the best overall design which I think was partly due to the JP being so ugly. The J&P is suppposed to be incredibly loud although I have NEVER heard anything as loud as the two Vais's I use. Not wearing hearing protection (I wear plugs AND muffs) is absolutley out of the question. I accidently shot it once with my muffs raised and it was worse than any rock concert damage I have ever encountered (and I have been to a few). I have n personal experience with the JP but he had nothing bad to say about them as far as accuracy.
