We have five company cars and two pov's. we put snows on most of them. The ones we don't we use Nokian WRG2 year-round, an all-season with the Mountain/Snowflake (severe snow) rating. We've used Nokians, Michelins and Blizzaks.
CR seems to do most of their winter tire testing at low speed in a hockey rink. They also, by their own admission, use other criteria for their rankings than shown int the tables - which is why, for example, the X Ice3 is ranked higher than the X Ice2 even though the X Ice 2 was better in several of the tests shown.
The Nokian Hakka R has a thicker tread than the Michelins. They tend to last at least a season longer than the Michelins on our fleet cars. This makes them both more effective than the Michelins and less costly to own.mYou won't learn this from CR
The X Ice is a good choice if you drive a lot on dry roads or don't have a Nokian dealer in the area.
The General Altimax Arctic is a good choice if you mostly drive on snow-covered roads or are willing to sacrifice dry and wet road handling and braking in return for low cost.
We've had OK success with Bizzaks but had the older model. Like the Altimax they had good snow and ice grip at the expense of noise and dry and wet road performance.. I believe the WS70 has better dry and wet road performance but we haven't bought any lately.
If "All Season" tires could pass the Severe Snow performance tests, they would. They can't. The guys at the Team O'Neil winter driving school refer to them as "no seasons" or "no reasons." If you live in the snowbelt, the Nokian WRG2 or WRG3 are vastly superior in snow than any all-season and can be used year-round.
We made the mistake of pitting some Michelin Pilot A/S on our Mazda minivan. After the first snow my wife boycotted. Take CR snow and ice ratings for AS tires with a grain of salt.