We have an AWD that we drive in the North Carolina mountains in the winter with no problems at all. Admittedly, it's not the Rocky Mountains (or the Sierras) but we've been able to keep going when many other 4 wheel and AWDs cannot. We have some steep hills that we can climb (and descend) with up to about a foot of snow and made it through. I especially like the anti-skid as it cuts in when needed and works to keep us out of trouble. This is our second AWD Lexus and while it may cut into the mileage a bit, I would not consider a car without it.