i used the klim googles with the polarized lens twice, one day was cloudy, just trail riding due to snow, no fogging even when stopping several times.....2nd ride was very snowy, foggy, with driving wind and snow dust across the ridges, no fogging even though conditions were such that i expected them to fog...we stopped several times to check our new sleds for clutch heat etc. and ended up talking for 15-20 minutes without taking off helmets and googles due to falling snow etc.....still no fogging, even though we weren't working hard, we were riding pretty hard mostly on roads with 2 ft or more of powder...nearly positive that any previous google i've used would have fogged..