It's been a few years, but I had a set put on my XJS after a snowfall where the car was sliding all over the place. A week later, while I was at work, it snowed about 14". There was a Dodge Dakota 4x4 in the lot spinning it's wheels. I thought, o !Removed!, I'll never get out. But the Blizzaks did the trick. Got out with no wheel spin at all.
This y ear, I put Yokohomas on my XF. They did the trick, too.