They don't handle snow at all yet. There is no question that will be quite a hurdle to cross, but I doubt it will be for the reasons most think. My guess is figuring out where the road is at is going to be the hardest part; where I bet most people think it is "how do I drive on ice". Without impatient, jacked-up-4x4 drivers driving a twice what conditions warrant, it is just a slightly different calculation of static and dynamic frictions.