 I bought my 2005 GLS TDI new after test driving a base gas model.  At the time, the gas and diesel models were the same price, the diesel mileage was far superior, and the cost of diesel was quite a bit less than gasoline so this was a no-brainer.  Now, diesel is often more expensive than gasoline, and sometimes even 15-20% more, so the diesel advantage is not what it once was.  Still, I like being able to go almost 600 miles on a fillup, and I love the power, reliability and longevity of this engine.  I have 175,000 miles on my Passat and have not had a single repair bill outside of scheduled maintenance.  The most expensive maintenance is the timing belt replacement every 80-100K miles. The car has excellent pickup, not as peppy as the gasoline Passat, but much better than most cars that I've driven, including V8s.  The 10,000 mile interval for the synthetic oil change offsets the higher costs associated with changing the oil.  This service, like most, is best performed by the owner, the dealer, or a shop specializing in German autos.  Maintenance costs are slightly more expensive and servicing establishments more limited than Japanese, American, Korean or other cars, but the Passat spends very little time in the shop.  I think that this has been an extremely economical car, but it drives as well or better than cars costing quite a bit more to purchase or maintain.