I saw these pads last week at Sno Pro Jam (a Professional Ski Instructors' Association event) at Killington VT. They seemed to work well, although I never personally used or needed them, as I seem to be alright without heaters in my regular ski clothes and boots down below 0 Farenheit. The guy who makes and sells these is a very independent businessman (maybe even a little crusty), so be patient in talking to him. They look to be a very nice product. He solicited me to rep these, but I don't have the time, or inclination, so I have no financial interest in them.