Wow...I have to say thanks to Chris at SOS and Aaron for helping in my selection of the JGTC. I would have been disappointed with anything quieter. If you enjoy hearing your exhaust at all RPM's then the JGTC is for you. Amazingly, with the windows up, the cabin noise is not much different from stock. With the windows down, the sound is loud, but not overbearing...After driving around for awhile, it's easy to tell that from behind, the sound is incredible...It gives an awesome "echo" off of everything you pass (other cars, underpasses, etc.) It has several distinct "pitches" as you move up through the RPM range. At WOT it simply wails like a race engine should. As far as any power increases..tough to tell..Feels faster, but that could be all in my head..I definitely noticed that my throttle response is a lot more crisp..I especially notice this when starting off in 1st gear...The only negative side to the JGTC: My gas mileage will decrease dramatically because I find myself spending a lot more time in the upper rev ranges..No problem accepting that trade-off.