I bought those tires mostly on the basis of other reviews. I didn't want to buy a dedicated snow tire/wheel set for my M5 and wanted something to work in snow and summer.
Bottom line, this tire's traction in snow is very decent... On ice, it's not that good as I expected. The ride is soft and cornering isn't that great but again this is an all season tire with more emphasis on snow/wet traction so for that it's very good. On ice, the car couldn't climb my driveway... But a snow layer, it climbed with no issues just don't let the tires spin.
However, if you drive a high performance vehicle like me (BMW M5), you are better off with a dedicated winter wheel/tire set... Keep the Michelin Pilot SS on the original wheels (mine were really worn)... The ride can't compare and for a driver who enjoys all the proper feedback, Pilot SS are just amazing... So it's not worth ruining 3 seasons of the year in favor for one season (winter). You will be missing a lot in ride feedback and agility. If you can afford and have space for a winter wheel set, go for it.
Other than that, it's a great overall tire but me personally, once they wear out, I am not buying another.