Of these cars, the Porsches are the only ones that have NEVER left one of my family members stranded. The NewBeetle (just bought to replace the '77 924 for my youngest daughter to commute this fall to college with) broke down due to a failed waterpump. The Audi twin turbo took a crap on my wife and needed to be flatbedded home (fuel pump took a crap). The BMW 325i is a great car with 287,000 miles on it, but the radiator neck broke stranding my wife about 4 yrs ago (this what I DD the most as it gets about 27 mpg).
Bottom line is that the P-cars, all with well over 100k on them, are well built in regards to major components and if you buy a clean one that has had the timing belt and clutch replaced, you should be just fine.
the "pretty good" apples
the "bad" apple