I own a MB, my third one. An R350 bluetec diesel. The previous cars were pretty much maintenance free. This one has been a maintenance nightmare. Are they all or did I just get a lemon?
You picked a bad brand, and a particularly bad model
The R-class was always something of a dud
Your not making me feel better about my choice! 
Other than maintenance I love the car. Seats six and with the seats down can stow my bike. Drives great on the highway which I do primarily. Any suggestions for my next car?