I currently have a Turbo Smart Supersonic dumpvalve. If its noise you want and as above tuneable then, Id say you cant go wrong with this one. Had the first Bailey twin piston d/v, just didn't have the same effect. Must admit when I first put it on I was disapointed as had spent £200 odd quid for a dump valve and was quiter than the Bailey, however after taking it to PTS for a tune they got the bloody thing screaming at me, so as I said if you want to be noticed then you cant go wtong with this. Gota ask yourself if you can warranty spending that sort of money on one.