We have one of these, but I haven't driven the 170 engine. The only comparator I can give is a 2004 vintage Ford TDCi 136 engine, and would say they feel similarly rapid when revved but the Audi is much better below 2000 revs. The Audi will pull happily from about 1200-1400 revs, and the arrival of boost is much more gradual. I think you'll only really notice the difference from the 170 if your driving style means regular excursions beyond 3000 revs.

It's honestly not as much fun to drive around corners as a Focus hatch - it's natural habitat is the motorway, so make the most of the engine by relaxing at the wheel and getting > 50mpg on a longer run. It's a very quiet car and will cruise happily at any speed you are realistically likely to get to on UK roads, You'll have no problems on slip roads or A-road overtaking.

You don't get a spare wheel - there is a battery in the wheel well. And the driving position is sloppily designed for a car that sells this well in RHD as the pedal box on the right is too narrow, leading to offset pedals (which you do get used to) and quite a narrow gap between clutch and footrest which will always be a problem if you wear big shoes.