I should also add that buying a separate set of rims for winter tires and swapping them out seasonally can be fairly cost effective, as well. As long as you have the space to store the unused tires and can do the swaps yourself, your only real expenses are upfront costs. Once you get into the swapping cycle, you're not eating any costs really because you're saving mileage on the unused set. My summer/all season tires last much longer because they aren't used during the winter and vice versa. So instead of buying 1 set of tires every 3 years or so, I'm really buying 2 sets of tires every 6 years or so (using overly simplified math here).
Then again, I have a large garage, a tire mounting machines, and teeny 15" tires that made for a mere $450 investment for me ($300 for the blizzaks, $150 for the rims, self mounting/balancing). This can be near $1000 for most people with larger tires, no expertise in mounting, and most importantly those damn federally-mandated TPMS sensors (which my car does not have).
Anyway, something to think about. I can't stop raving about my blizzaks.