Why not? This tire design (lug void in outer tread, tight inner tread, reasonable siping) is exactly what you want in winter conditions on a 4x4.
I just installed them less than a month ago and I've been very impressed. I've owned 11 4x4s (down to 3 currently) with at least twice as many different tires, and the combination of an 80 and duratracs is the best I've driven in the snow.