The APR really was all that they claimed it to be. I didn't have a single CEL or any other drivability issues with the car. It even felt better on the low end, like when you're looking for a parking spot. I really would give it a shot, although it does sound like you might have a boost leak, so get that looked at. I was spiking around 22PSI with the GIAC software and it would taper down to 15 or so around redline. The APR stays around 20PSI as the RPMS climb staying right at the surge rangel of the compressor, then the boost climbs to about 24-25 PSI as the rpms increase. The car was tons stronger in the top end. I had pretty much the exact same setup as you, and I even went back to the stock DV from the AWE. The car really responds better at part throttle with the stock DV. With the AWE DV I would see the boost vary up and down over and over when going up inclines. With the stock DV, the boost would hold steady. If you have anymore questions, hit me up on the vortex, I spend much more time there. Now I'm spending a bit more time at bimmerboost! 