In reply to Tom Last: in terms of space, the saloon is a lot more limited that the Avant due to the narrow opening (even though the seats go down). An A3 Sportback would be better (space wise) than the saloon as well.
Make sure you’re happy with the S Line’s hard ride (test it on some normal potholed roads not the smooth track the salesman will take you down!). And make sure you don’t mind Audi’s offset pedals - they gave me backache!