Go with the Skoda. I think Skoda have the best build quality of any of VAG cars at the moment - Audi and VW are pretty dreadful and have gone through a spate of terrible electrics (well have on our fleet anyway).
Ford seem to have got the electrics sorted as much as they ever do but the number of Fords you see on the road of all ages with dodgy grounds, blown bulbs or just plain stuck at the side of the road leads me to believe that Ford learn their electrics skills at the Alfa Romeo school of wiring.
Having said that I've just ordered an A6 as its the best of a bad bunch on our list and I wasn't allowed to "down grade to a Superb" (upgrade as far as I'm concerned) due to a stupid company car policy.
The Skoda was more comfortable - more rewarding to drive and a nicer place to be.
As far as snow goes though - have a look at those autosocks - I got a set this year and they are brilliant - I'll warrant my car is one of the worst on the road in snow too