So are blizzak tires that good?
As a winter tire...? Oh yeah! I am not lying, the event organizers would check your tires before assigning you to a racing class. They specifically look for Blizzaks! Here is a snippet of what TireRack has to say about them:
Do Bridgestone Blizzak Tires Live up to Their Reputation?
The Tire Rack has been the largest single source of Blizzak studless winter tires in the United States since their introduction in 1993. We have tested them on ice and in the snow, as well as driven on them through South Bend, Indiana's "mild" and "wild" winters. We have found that no All-Season tire or other winter tire has matched the Blizzak's confidence-inspiring combination of deep snow, packed snow and ice traction.

Here is the link for more info so you can decide if they are biased salesmen: http://www.tirerack.com/winter/tech/...jsp?techid=116

A great 1997 read without bias: http://www.usroads.com/journals/aruj/9712/ru971202.htm