well first of all we used it for about 3 days non-stop constantly lol that isnt going to help but....i came to the conclusion of all the heat build up in the manifold and turbo out the engine, sort of sat in the restriction of the 3rd cylinder runner so sort of munched the thrid piston ring as it started to smoke the next couple of days...also secondaly, the turbo now has quite a bit of shaft play due to using the Bee*r for ages... in conclusion...i dont think its a problem to use it if 1. you have a decent aftermarket manifold, and obviously no cat....and 2. use it in moderation, i.e everynow and then when you go to santapod or whatever, dont use it on the street every second like si did...and finnally once used, make sure you fully cool it down properly after use, and before you use it again...as massive heat, and then instand coolness can crack the turbo wheels...\ Rob