I have recently purchased a 2003 RS6 after much mooching on the forums. The old man had a few as well so I sort of knew what I was looking for .
No issues so far apart from the rear window wiper not working and filling the battery compartment up with washer fluid but thats all sorted now with a replacement from an A3 (It wipes the wrong way now though lol).
It will be due its timing belt change in a few thousand miles as I dropped the ball there and will be looking for muchos info with my friend the search bar!
Only thing I really want to know is the tool codes required for the timing belt? i.e. the cam locking bar, tension unit locking pin, etc.
Might see if I can blag myself a second hand rosstec as well if im lucky.
Cheers and hope to hear from you guys

Pete