I re-routed the wasegate lines on mine 2 months ago, with boost pressure helping the spring. The gtx is pushing 30psi in the midrange now, falling to 25, not bad considering the Turbosmart has a 1 bar spring. It was road tuned so I dont have a new graph but the power curve seems flat from 4k to 7.5k. Exhaust temps in the manifold are very low, I havent seen more than 700 degrees and that is on lean cruise.
Very happy with the Garrett and i'm amazed how quick it can spool to 30psi when I drop back a gear. Its absolutely silent too, great stealth setup.