Update = have no idea how we ever did without them. The studded Nordfrosts are the best tire I've ever used in my life, in these winter conditions. We don't see bare pavement until around April, so they're wonderful. It's like driving in the summer - quite fun to be out in ridiculous weather, with the roads looking like a mirror and/or a hard-packed snow chute, and not having to worry!
Liked them so much I bought a set of Nokian Hakkapellitta LT2 studded tires for the truck (Gislaved didn't make them in truck sizes) - they're less impressive, but still not bad. In 4WD, they're unstoppable.