I've owned quite a few watercooled VWs. They're known by their chassis designations: A1, A2, A3, A4, and, the current model, A5 (not to be confused with the Audi cars that are called A3, A4, A5, A6, A8, etc). The A1 chassis debut back in 1975 or so and was replaced with the A2 chassis back in 1985. The A3 chassis replaced the A2 chassis in 1993, I think. The A4 chassis made its appearance in the VW New Beetle in 1998, I believe, then the Jetta and Golf were redesigned in 1999 on the A4 chassis. The A5 chassis was introduced in 2005 as the current model Jetta. As you can see, each chassis designation can have several car models made on it. The A1 had the original Rabbit, Scirocco I and Scirocco II, Jetta, Cabriolet, and the Caddy (pickup). The A2 had the first Golf, slightly more round Jetta II, and the Corrado. The A3 had the Golf, Jetta III, and restyled Cabriolet. The A4 had the New Beetle, Jetta, and Golf. The A5 has the Jetta, new Rabbit, Eos, Tiguan, and GTI. I believe that the Passat is still designated a B6 or B7 chassis.
Quality and reliability have improved with each new chassis and so has standard equipment. The first few years of any new chassis or model will always have problems but the later year cars seem to improve on these as they figure out how to make the cars better with experience. Having said that, the A4 cars seem to have suffered from the most complaints about quality and reliability for some reason. Fortunately for me, that is the one chassis I have not owned, though I have driven a few.
My current car is a 2006 Jetta GLI. It's been a wonderful car so far. The only problem I have had with it was an airbag light coming on that the dealer fixed. Other than that the ignition switch sometimes does not read the security chip in my key so the car doesn't start but I just need to remember to push the key up as I turn it to start the engine. I really need to bring it back to the dealer to have them look at that but the car has been absolutely a blast to drive so I've not had any thoughts about bringing it in.
My '98 Jetta TDI had 167,000 miles on it and it was going strong before I wrecked it on a rainy day. Had I not crashed that car I would probably still be driving it now.
I'm sure that, with the current model being relatively new to the market (the oldest examples being about 5 years old, now) that we're hearing about problems with the previous generation cars. I've belonged to a few forums for the Mk V VWs and VWs in general and they don't seem to have a whole lot of problems that the owner didn't cause in the first place and forums are typically places where you hear about the problems, not the "My car has XX,XXX problem free miles and I love it" type of posts.
Sabrewolf, are you a member of Fred's TDI Club? I am member 67 over there, though I have not posted there in years. I was a moderator there for a few years but couldn't dedicate the time needed to do an effective job of it so I gave it up.