We're in upstate New York on vacation skiing and the X7 performed like a champ on the stock All Season Runflats.
Atop the 20"
and the following 8" we got
another 6" and on unplowed roads and parking lots at our resort the wheels did not slip and at no time did I feel like we were going to get stuck. That's ice under hardpack with 6" of fresh thick snow and untreated and the X7 was carving the road on inclines and declines as if I had snow tires on.
I'm normally a big proponent of winter tires but, got to be honest, I don't think it's necessary with the X7. It's proven that in NYC with our typical slush/few inches its got it easy and now in the deep stuff too upstate, wow.