If you want an exhaust that is close to stock but a little deeper and throatier... go the Bastuck route.
If you want one that was meant for the M3 right out of the factory... go the Eisenmann route. You can't go wrong with the Eisenmann. It is just incredible.
congratulations to the guys that just put it on their cars... you know who you are... see you soon for your wheel set up.