I also own a 2013 VW Jetta TDI Sedan. It gets around 40 mpg on my mix of driving and if strictly on the highway it returns close to 50 mpg. They really aren't broken in until you have 10K miles on them so I expect improvements as I am just approaching 5K miles. Check out TDIClub.org and you will find that many owners of 2012/2013 Passat's and Jetta's are already approaching 100K miles that are pretty much trouble free.

I love the sporty driving feel of my Jetta and the fact that it still comes with a full-size spare tire and doesn't require Ad-Blue (DEF) as most other Diesel vehicles.

I agree that with the complexity and new technology of most new vehicles you need a warranty. Also, if you look at warranties offered by manufacturers, they generally don't exceed 7 years or 100,000 miles. An exception would be Mercedes who offers an extended warranty on their CPO vehicles for up to 7 years and 135,000 miles. That should give you some kind of feel on how long you can operate modern cars these days economically.

I really think that these days driving a car is almost like driving a laptop computer on 4 wheels.