i run a CT 350pv with the ESR trx-5 center mount. you will find that on teh cookie cutter PV's (from asking other owners)you will generally loose a little on the top. understand that in general, 2-stroke porting is a give and take of top end and bottom end power. As well the addition of teh powervalve simply smooths out the powerband and DOES NOT magically give you power where it was never ported for it. for instance if you have a cylinder ported for only top end power, teh PV will NOT automatically add power to your bottom and midrange. But it will however smooth the powerband and take away that "light-switch" effect. Now, this smoothing of teh powerband will naturally raise your HP in areas along the upslope of teh power curve (imagine looking at a dyno read out).
As mentioned earlier in my reference to the "cookie-cutter" pv's loosing a little on the top: in order to maximize the function of teh valve the builders will generally port teh jug with a bias for the bottom end. keep in mind that several factors dictate the characteristics of a 2 stroke motor: pipe, exhaust port hieghth, compression, squish band, transfer ports, etc. Teh powervalve ONLY manages the height of teh exhaust port.
now back to teh pipes: like i said earlier i run an esr trx-5 pipe. for what i do(duning) this pipe suits me just fine. power is available wherever i need it. could i use more power on the top? i wouldnt mind it... is there enough power on teh top?.. YES!!! i hope this helps you in your inquiry