This M5 was just spied on the Nurburgring and coming in/out of the M Test Center at the Nurburgring. Does it show the beginning of testing and development of the BMW M5 CS model? If so, this variant would follow in the vain of the already released BMW M3 CS and M4 CS. It wears the M Performance Pro Spoiler and also features M Carbon Ceramic brakes, standard on the M3 CS and M4 CS. An eventual M5 CS would feature more aero parts (mostly M Performance Parts) than seen on this potential early prototype, unique CS wheels, and different (non-rolled) exhaust tips.