My A3 has gone in for a new seatbelt under warranty today and this week I was given a Sportback 170.
But I ain't too sure it is tbh. The first tell tell sign is the exhaust- it's not the shiny metal one- it's the same as my 140.
Is there a definite way to find out? it felt faster, but it could have been psychological if you get what I'm saying!
Sportback is uglier than the 3 door though no question but much more spacious and the doors shut with a good thunk whereas the 3 door version's doors don't quite sound so "thunky".
I will need a 5 door next so I guess I'll have to live with the little uglier aspect!