My quest to select an aftermarket catback exhaust system began when I took delivery of my Subaru Impreza WRX STI in March of 2005. I realized that the STI was quiet and that the exhaust, which featured a stylish chrome tip stamped with the STI insignia, emitted no real performance sound. Even when I stomped the gas and the turbo spooled up, the intoxicating boxer rumble barely...