Both the TSI sedan and SportWagen are eligible for a $1300 federal tax credit due to their frugal fuel consumption. The EPA has rated the TDI cars at 29 mpg in the city and 40 mpg on the highway, but those numbers didn't make Volkswagen happy. In independent testing, the TDI Jetta recorded 38 mpg in the city and 44 mpg on the highway.
Pricing for the Jetta TDI sedan starts at $21,990 and the SportWagen TDI begins at $23,590. That's about $2000 more than a similarly-equipped Jetta sedan and a mere $700 more than the 2006 Jetta TDI sedan. Despite diesel's recent surge in price, it looks like you could still more than pay for the TDI with a few years of driving.