Like they said above, it depends a lot on what kind of use you intend for the car.
I still have my somewhat unfounded doubts about Audi's since I always still hear both favorable and bad reports, but no personal experience. But based on road performance and styling I'm positive I really would like the car a lot if it proved to be reliable ...while the A's are basically very nice, my heart lies with the S models, S4's are extremely nice. My long time expert foreign car mechanic still keeps saying the cost of maintenance is significantly higher for most European cars than comparable Japanese cars.
The 300ZX is a very cool interesting car and I would definitely enjoy having one but would never think of using it as a daily driver. I'm a die hard motor head and I would have to start cranking up on the twin turbo model (the only one I'd get) and one thing leads to another to another ad nauseum. A little over six years ago when I was shopping for a fun sporty car and which I intended to modify to a limited degree and already knew I would take it to high performance driving events at various road course venues in the Northeast U.S., I looked at quite a few 300ZX twin turbo models and a handful of other cars in that class as well. Though the initial cost was somewhat higher, I ended up buying a low milage '95 Toyota Supra twin turbo (even though I liked the 300ZX TT better in some ways) and I have never had even one millisecond of regret and actually, the car has exceeded all of my expectations by a huge margin. Now six years later it has never even hic-up'd wrong once, I barely have to do anything to it except change the oil and normal maintenance, for the last few years it has been reliably cranking out well over 500bhp, when I track the car almost nothing can touch it except hardcore race cars ...the best car choice of my life. Good luck with your decision.
PS: know theyself ...my ad nauseum part continues, I have parts laying around now and on order to step it up a couple hundred more hp but that will be the end
