All nice cars, but rickety - with the exception of the Audi.
I've got an A4 - it's comfortable, well-equipped, safe, and looks great.
Plus, there's the added appeal of it not being a (mitsu, honda, normal normal normal)
I cast my vote for the S4; Black. Very black.
And might I add that (i see you bought a truck? ick.) it's bodystyle is timeless - mine's a 96, and people always assume it's brand new, and that I spent $40 grand.
I got it for less than ten.
/end.