I have had my Jetta Wagon TDI for 3.5 years now and basically would not trade it for anything out on the market. It was relatively inexpensive to purchase new in 2004, especially compared to other comprable cars on the market at the time, especially comparable WAGONS on the market (subarus and such). I drive it to work every day and have no complaints with 43 avg mpg. I carry my two 50 lb dogs in the cargo area regularly and they have more than enough room to be comfortable. The back seats are lacking in footroom but since it is just me, I have not been too concerned with that. Don't know how well carseats do in it yet either. My husband plans on using it as his commuting vehicle in future.
There are a lot of little rattles and noises from loose fitting pieces (aesthetic not essential) when driving, wish they would build it better fitting.