I've had my Golf GLS TDI for three years now and I love it. The diesel engine runs great. I use biodiesel for fuel and average 38-42 miles/gal. The turbo provides quick pick up. The manual transmission is fun to drive. It has enough trunk space for storage. It is the perfect car for day to day commuting and to able to fit into tight parking spaces. As with many VW diesel cars the engines will last forever, but the small electrical components are not reliable.
The gas mileage is awesome. I get 500-600 miles on one tank of biodiesel! I love the Monsoon speakers, manual transmission, and the interior/exterior design.
Add a front seat arm rest. The sunroof broke six times before the dealership could figure out what went wrong. Oil changes are expensive. The seats are a little hard on long trips.