There is one for sale in the latest edition of unique cars - page 143. its in Adelaide, has compliance, states 34,000km's asking $37,500.
I believe most of the rs4's are auto which would prob suit your towing needs but I think you were really after hands on experience - sorry haven't seen or driven one - pretty thin on the ground at this stage. The 260RS must be a temptation!
Edit - Sorry when i reread the ad its not turbo.