I did a lot of research before buying this tire. It turned out to be an excellent choice. On snow and ice I always have the Auto 4 on no matter the tire so never had a slipping problem. The only time the tire was not up to the task was in deep, hard packed, drifted snow, but few tires are. They had 50,000 miles on them when I replaced them with Firestone Destinations MT's for the winter. I would have put the AT's back on in the spring as they had plenty of tread left on most of the tire, but my suburban developed an alignment problem and wore the inside tread down too much. The algnment was not the tires fault, but mine for hitting potholes too fast.
I think Tire Rack should have a rating on deep, hard packed, drifted snow since that is where I have seen most AT tires fail. I went to a MT for that very reason as we have 2 miles of it to get through. I have yet to see an AT tire have too much trouble with powder snow unless the vehicle is pushing the snow with the front of the vehicle.