Stroker (2.8), E85, GT RS's, split dumps, HKS front pipe and Kakimoto Full Mega N1. It was the most intense, obnoxious sound. It was literally louder than venting to atmo gates... That's the good part of you like that sort thing.
That cat back on a stockish car sounded no where near as barky and loud.
It also was awful for any type of performance. Funnily enough, the last 5 items on that list have been pulled off the car.
Kakimoto sound great but hold the car back.
* ignore second gear. It was having ignition issues in anything but first gear.