[Turbod]

Not reading everything everyone else has posted so far. xDrive has secondary cats so the car is a little bit louder than when the valve is open but not bad at all. The smell difference is very minimal due to the secondary cats. For people reading this without xDrive, the cold starts are decently loud and the car under WOT from the back is loud but inside the car is just loud enough to be enjoyable. Obviously if you have no cats there will be a smell but you'll only notice when stationary for a period of time, more so when the windows are down.