I'm a fan of my Pirelli Winter Sottozero S3
definitely a relatively snow-biased performance tyre (e.g. compared to the more performance-oriented Pirelli Winter Sottozero Serie-II). But I'd concede that for the worst snow conditions there are probably better choices, like the Nokian above.
What is particularly good about the S2 is the resistance to hydroplaning - much better than any other winter I've had. But probably no surprise, given the obviously high proportion of contact patch that is carrying deep drainage channels. Yes, this at the cost of dry handling but terrific in heavy rain and standing water.