I purchased the car with 255k on it. I have driven it for 3 years now and the mileage now sits at 448k. I once read in one of the snooty Mercedes forums that "the legendary half-million mile diesel is largely urban myth." I expect to go well beyond this number. I don`t baby it either. I sometimes go up to 16k miles between oil changes and pour used vegetable oil right in blending it with diesel in summer only of course. This has had zero effect on performance. A German tank!
Somehow, I realized that my car collection was more like a guzzler collection except for my 1998 Corvette. I own a new BMW M5, a 1999 GMC Envoy, a 1988 Mercedes 560 SEC, and a 1994 GMC Jimmy, and I soon realized that nothing had good gas mileage in my garage, except for my motorcycle and Corvette. I was going to buy a Honda Civic or a Toyota Corolla, but I am 6'3" and 260 and needed leg and hip room. I discovered the MB 300SD by sheer accident, but wow, I am getting about 500 miles per tankful in the city and 600 or more on the highway. Not bad for a full size luxury sedan. And throw in all of the forums that help with everything except the most difficult of repairs and you cannot lose.