I'm just gonna leave my exhaust stock. The guy that bought my Jeep TJ has an '03 WRX wagon and he picked up an Accessport, intake and aftermarket exhaust (Forget which). He wanted to show me his car and took me for a spin. It sounded OK, but was pretty loud, I can see how it would get annoying quickly, especially on the highway. Anyways, our neighbor my wife's friend was over and they were talking; when the guy left with his WRX, neighbor girl commented "What is he, 17?". Gotta admit, I laughed. I'm 38 and WRX guy's around 40 as well.
IMO, if it's not a V8, it's best left quiet. Some of the ricers that run around town, I'm actually embarrassed for them when I hear their cars. More embarrassed that they don't realize it sounds like shit, really.