I think the 4 door formula will appeal to a wider audience. The Audi A3 sedan will also be 4 doors, maybe its not such a big deal to do both version, I personally like the 2 door in this size of a car.
As far as the Benz, I like the front, not much else. Still never a fan of MB so that might also be.
Hey more choices and more competition is always good for the customers so I'm all for Audi and MB joining the 2 series in the segment.