2004 Audi A6 2.7T S-Line quattro AWD 4dr Sedan (2.7L 6cyl Turbo 5A)
If you're dumb enough to buy a $50k car and complain that it costs a lot to maintain (when you only paid 20k for it) then shame on you. This is a phenomenal car and beats the pants off any comparable, or even brand new, car you can get for ~20k. I've had 2 and loved them both. (148k miles, and 22k miles) The car is fast, comfortable, reliable (if you keep it up), and an awesome daily driver.
the things not listed in your common report: simplicity of design, advanced functionality, aerodynamics, steering control, durability of interior, ease on eyes displays, automated stereo, nav, environmental controls...
dash display lights fad afteer ~45k miles (in every one I've seen)