For me it's a toss-up between the 120i and the Golf GT. The Astra - although not ugly - just seems like it's going to look outdatd pretty soon. It's performance was more than respectable though! The Audi, again just looking at the car I seem to get bored fairly quick. Nice interior but that's about it really.
The Golf looks great from the inside, although the interior design is not to my liking. The BMW has the best designed interior of the lot IMO so that's a bit of a plus when comparing these sorts of cars. Exterior .. the 120i also wins over the GT, especially since it's the 3-door variant. One big let down for the 1er is its performance figures.. but then again, you wouldn't be buying any of these cars if performance was your priority.
I'm with Tycoon though.. I'd definitely wanna tick the 'M-Package box on the options list.. coz with that look it's a no-contest hands-down win for the 1er.