Timing belt on a B5 A4 should be done every 70K mile's, no more than 80K. Front control arm bushings tend to go bad and the whole arm has to be replaced, all 8 arms cost about $560 on ECS tuning and that's if you can install them yourself. AWD is great and they handle well if you put a suspension on them. They're slow stock, at least in 1.8T trim, but with a chip I took the car from a 16.3 stock to a 14.9, and I needed a new clutch(could only launch a 2.21 w/o the clutch slipping) I think if I had a new clutch and could launch hard it would have run in the 14.3-14.5 range just chipped, maybe lower. The maf goes bad if you don't change the air filter religiously. Other than that I thought the A4 was a great car, but I am my mechanic so maintenance is just the cost of parts and a weekend for me.

German cars are for people with the money or the knowledge to fix them. If you are competent with fixing cars or have a really good paying job you should be fine. Otherwise get the japanese car.