My DD is my AAN'ed 1990 80 quattro. In many respects I love it but there's one big issue: the "quality parts" thing.
I basically redid the whole car mechanically 3-1/2 years ago. Brakes and suspension in particular got almost all new components, an exception being the calipers which were rebuilt (by "professionals", not me). Since then I've had to replace all 4 calipers, the rear diff rear mount failed completely at < 1 year of age, and the strut mounts are now questionable. I've been lucky enough to score a few brand-new calipers as replacements but those are becoming rare or nonexistent. The diff mount I replaced with poly since I couldn't find a good rubber one - everything I could find is made-in-China junk. Other things like diff lock actuators are nonexistent new, and not always very rebuildable, even with a lot of creativity.
I will say that other than the above, I love the car and it's never even come close to leaving me stranded, unlike the 14-years-newer A4 my wife bought about a year ago. But knowing that when any given part fails I may have no choice but to replace it with one of much lower quality is not fun...

I also believe that at 300 HP, with all maintenance in order I would not compromise drivetrain reliability. The biggest thing I would be worried about with dailying an older car like after all suspension, brakes etc are sorted, is the interior. Finding a clean interior is hard enough, but making sure it stays in good shape is also not easy, especially putting a good amount of miles on it. In my mind I would swap in a nice bluetooth headunit with some decent speakers. I think I have been spoiled by the OEM radio in the TDI, because that is one part of the car I love.







