Ice! Not any better than an all season tire on smooth ice. Ok on roughened or textured ice, dry snow and hard pack. No good in wet snow on thawing hard pack driving forward, but fair in reverse. The directional tread probably explains this. Other sizes are probably getting the more favorable reviews. Going back to the better Michelin X Ice.
The difference these tires make is immediately noticed. Road noise is greatly reduced and the smoothness of the ride is impressive. In well maintained roads it feels like you're not moving at all. Friends that have drive the Sienna the first thing they notice is the smooth ride and ask what kind of tires it has. Driving in snow is pretty good. Traction in deep snow, or icy conditions is not the best, but is very good in torrential rain. Handling is also very good. I had my tires for 50,000 mi. During a 3 year period. Tread is down to about 5mm. So I'm not sure if they will last the 80,000 mi. expected. Overall I'm very satisfied with these tires and will buy them again when it's time to replace them.