Direct injection looks like it may pose worse reliability issues than turbo in the long run.
It seems that is mostly just Audi/VW having a crappy implementation of it. A lot of engines have had DI for a very very long time. It's being marketed more aggressively of late, but the first DI motors were invented in the 20s, were common on WW2 aircraft, and was a feature of the 1955 Mercedes 300SL. There are now heaps of cars that feature DI, and very few of them appear to have serious problems, aside from the notable issues with the Audis and to a certain extent with BMW and Porsche.
I love German cars, I'm a bit of a BMW fanboy to a point, but it's something to think about. It is interesting to see the differences in implementation. The Speed3 MZR setup (as well as Speed6) is apparently a superior implementation of DI, as the huge carbon problems seen on the german implementations seem to be far less common, and the vehicles are reliable over an impressively long period of time.