I'm still on stock Conti's. Not my first set, of course; I took those off at 60,000 miles or so. I have had pretty good snow/ice traction so far in three winters, but having never compared with snow tires, I can't say I'd know the difference.
I did have some trouble on my ice-covered dirt road today, but for that I just slipped on two Autosocks and was back in business. I've driven on snowy/slushy highways, and the Conti's have been ok. The ABS and ESP help a great deal.