 The biggest disappointment is with lack of traction.  You get on it with traction control off, and the tires spin. With ATC on, the car responds by actually coming to a halt right after take off.  You nurse the pedal, and start wondering if you should have saved a few $K and bought a SL600. The convenience features controls are very inconvenient as one goes through the menues to change settings, etc. Also a few electrical problems with the convenience package: Driver's seat won't retract on exit.  Car won't start easily if left parked for 2 or more days. "1-" or "2 Malfunctions, Convenience Functions Unavailable" is often displayed with no indications of the problem.  Then corrects itself