Like Denalio said, 'Best' is very subjective - IMHO, any of the snow tires mentioned in this thread are great. I have had Blizzaks, various Dunlops and Hakkapeliittas as snow tires on various cars over the years and they have all been outstanding and a vast improvement over all seasons. No one set of tires stood out over any other (maybe the hakkas on a RWD car).
Regardless of which set you choose: snow tires + AWD = in great shape for winter.