Slightly off topic, but:
I just had aftermarket S6 radiator fitted. Nissens brand, part number 60424, super cheap (like $200). VAG OEM part number 4B3121251D.
It's a direct drop-in replacement to the early RS6 one (if both tanks are plastic). With one important caveat: S6 is approx 1cm thinner, so less dissipation capacity. Use it cautiously in hotter environments.

If you have one metal tank in your original radiator, S6 is NOT a direct fit. You will need to redo the aftercooling path.

Just throwing this out here for everybody to see.