When I used to race MX back in the 80's, we used these pipes on our modified bikes. These bikes were 80-85 cc's, but I remember them as being good quality. It seems like PSI was big back then, but not now (maybe I'm wrong, but all you hear about now is FMF, Pro-Circuit, etc...). I'd say if you got a good deal on it, you shouldn't be disappointed. Put it on and twist the throttle!
Let us know what you discover...I'm all about nostalgia!
They are located deep in the heart of sconny. http://www.psiperformance.com/
All sled now, 10~15 years ago they entertained 2smoke and other bike stuff but now they are just sleds.
Their big air carb is hokum on a DB untill proven OTW.