Said I would get this up, so here it is. My 2007 WRX with Cobb TBE, Cobb SRI with heatshield running the Cobb Stage 2 91 OCT OTS map. Not the greatest video quality, my girlfriend was holding the camcorder in the passenger seat. But you get the idea of what it sounds like with the stereo off.
This is just the Cobb TBE, not the best but just a couple hard revs at work one day:
I have a video of the exhaust also I can throw up here. Yeah the BPV goes off often, even in 5th gear. That was a pull from 2nd to 4th and then back from 2nd to 4th again. It was cool like the first block when I put it in a couple weeks ago, now I make sure to have the radio on.