Spent two days up at Mt Rainier, WA. My wife's X3 had no issues in the snow. I think I floored it once on purpose to see how it felt, traction wise. It spun slightly and then regained traction pretty quick. They had a good amount of snow from what it looked like (I'm from Los Angeles so any amount is a lot).
Hankook Ventus v12 245/45/19 F and 275/40/19 R