I bought and wore these boots for the first time on my annual ski trip in Hakuba, Japan in Feb 2012 and they were amazing! I was so keen to test them out I wore them on the plane from Hong Kong to Tokyo and had no problems there. Feet were warm but didn't feel like they were going to over heat. The minute we hit the powder snow in Hakuba is was great. The sole has good grip even in slightly icy snow and my toes were always toasty warm. The average temp in Hakuba while we were there was about min. -20C and max. -5C (sorry, don't know what the Fahrenheit conversion is).
I always looked forward to putting these on at the end of each day after skiing. They felt like pillow around my feet. Great for walking around in powder snow that was at times knee-deep (I pulled the inner layer of my ski pants in the boot, and the outer layer on the outside of the boot just to prevent snow from falling into the boot as they only go up to your shins). I also bought the men's version for my husband and he loved his pair too!
I bought the pink ones (got lots of compliments!) and they haven't stained so far even though I was kicking around the snow a fair bit. I normally wear a US8.5 and I bought these in a US9 thinking I'd need the extra room if I wore thick socks. The US9 wasn't too big but a US8.5 would have been a more snug fit with thick socks on.
Overall, I would highly recommend this boot and can't wait for my next excuse to wear them!