true, even in alaska they are only legal from September to May, and they do wear the roads out faster. but the fact is, a good set of studded tires on a 100 series with atrac is an amazing rig in all sorts of winter conditions.
Certainly there are some situations where chains are preferable, like rock crawling interspersed with deep snow pits. But for 99% of all winter applications (especially where you want to go more than 25mph), a set of soft compound siped tires with studs is ideal. (The blizzaks and other studless designs are great most of the time, but on ice you need studs, and you never know where ice is gonna be.)
Yes they wear the roads out faster and they are not legal all the time and everywhere, but from a place where we get 20+ feet of snow per year (deep snow, shallow snow, icy snow, wet snow, all 31 flavors of snow) studded tires get the job done.
... though it would be cool to have a set of chains for breaking trail in really deep powder (if you could get them to fit on the front).
(Sorry for highjacking the "chains" thread just to sing the praises of studded tires, but really, they work.)