I just got my new ContiWinterContacts mounted. There wasn't much snow left for me to test them on. I had the wheels spin a bit, because I let the clutch out to fast, but besides that they were stable. They have about a 500 mile break-in period. I did drive through some snow, and swerve a bit on purpose. The steering is just a little bit less responsive, but it's a sacrifice to enjoy the Boxster all-year. When I went through some 4" powder, the rear of the car sort of slipped to one side (I think the snow just compacted and the car shifted) as I was turning but I didn't feel out of control, the car went right where I wanted it to. I am planning on finding a vacant lot tomorrow, to test them thoroughly.