Consider this post, and official vouch
Bought a 951MAX chip along with some other small upgrades, and the car feels great!
All I did for upgrades was some wastegate shims, vacuum lines, Manual boost controller, and the fuel pressure regulator. The car is still running at ~ stock boost so the performance should stay about the same, but the 951MAX chip made it pull harder and more consistant throughout my rpm range.
Somewhere along the way, he stopped my small intermittent backfires too (in between shifts on wide open throttle, dunno where they came from).
Thanks!
-Alex