The VR6 has a crazy timing chain setup thats super expensive to replace because its on the back of the motor and you have to take the trans. off to get to it. Also, there are coolant issues because of a crappy plastic transfer pipe (which is easy to upgrade to an aftermarket aluminum one).

The 1.8T 4 bangers go through a lot of ignition coils. Theres a recall on them now that should have been done years ago.

The 2.0's and TDI's are solid, but slower than molasses rolling uphill