that stock sound has a hell of an exhaust leak. in fact, it sounds exactly like mine did with its blown out cat and every single gasket being demolished
The magnaflow were the best sounding. Street series sounds like it could sound better and have a deeper tone in person and the axle back sounds loud only when you really push the revs.
depends on the setup. some exhaust systems are built for low down torque (h-pipes) which will improve throttle response while others improve back pressure and output at higher rpm’s (X-pipes). on its own an exhaust barely makes a noticeable difference in speed, might take a fraction of a second off 0-60 at most. mostly either for sound or to be paired with other mods