I just came back from my local MB dealer. I went there to take out a E500 which I will be writing a review on very soon.
Anywayz I'm browsing through the usermanual and get this, the Cd (aerodynamic drag value) is specified as 0.27. That's even lower then the KoenigsEgg, which is 0.29.
Here KoenigsEgg is making all this hubbab about how aerodynamic their car is and it's already been beaten.