I bought SW cat back last fall and put it on my coupe. Took about 1.5 hours to get everything lined up and leveled out perfect. Actual wrenching time to take off old and install new was less than 30 minutes. I was very happy with the deep, low growl sound. Then I got a wild hair and put on SW headers last week paired with the SW cat back...now no cats. Still sounds awesome. Way louder at idle and when you get on it (I can barely hear the supercharger anymore even with a CAI and smaller pulley). At 55-65 mph I don't think it's any louder in the cab than it was with just the cat back system. I'm very pleased with it.