[Gen-X45]

OC12, the TB doesn't add that much more volume (Sound note) to the cabin. However, if you go straight back from the cat's into an aftermarket system it's going to get loud and you may experience some vibration as well. I'm no expert on exhaust's, but they do move under pressure and if they are pushed up against the under carriage for lack of proper bracing it would be hard for the cars insulation to absorb the harmonics that would be generated by the two surfaces touching. Chase may be a good person to PM on this as he deals with a variety of exhaust systems with different set-ups. Right now it looks like your set-up is pretty much what I have. For my personal taste, it's perfect... idle is a low rumble, driving is smooth and you can talk or listen to music without any problems at all. When you jump on it, the car responds well and sounds great. I'm sticking with what I have for now. I'm almost certain that I'll add a CAI but I'm going to give the car about 2 more weeks to settle in with the TB because I only drive it on weekends.