It is a silly argument, and gmenounos, the B5 TDI is incapable of getting 50 MPGs unless you drove like a menace to others on the road. It tops out at about 40, most of the times an average of 38 is more realistic.
But, it was $28k brand new, I paid cash for it, and aside from the balance shaft upgrade, it has needed very little beyond scheduled PM. They do like outer CV boots, but those are really super easy to swap thankfully. And it still looks and drives as good as it did when new. It has been (and continues to be) a very good car.
My wife drives it mostly, I drive one of my Golfs... I now have three of them in operation, with another in the queue to be untooefed as soon as I'm done with the current pair of projects, a 2003 Jetta and a 2005 Passat wagon. I also have a gasser Jetta that I need to swap the engine on, but that isn't as exciting.
My carbon footprint reduction plan is to reduce, reuse, and recycle as much as I can. We can all do our part!