Definately not normal. For many years the maximum oil consumption rate was specified as 1 liter per 1000KM - right about 600 miles per quart. So the car is very close to that rate, but not quite over it. "Normal" oil consumption on this engine is more in the range of 1qt per 5K miles.

If the dealer won't look into it, have him call the zone rep and also contact the Mercedes customer assistance center directly - the 800 number will be in the owners manual. He may or may not get any satisfaction, but the experience will help him decide whether to purchase another Mercedes or not!

- JimY