This hat is insanely warm. I've found I can only really use it in very cold temperatures or very windy temperatures, maybe around 15 degrees F or below.I may be weird, but my ears don't like to be covered up unless the weather is really intense. I always end up flipping the earflaps up, making me feel like Robin Hood... I need to declare that I am a member of the Gore Mountaintechs product testing community, therefore I sometimes have the privilege of testing and reviewing sweet swag from W.L. Gore and Associates. Regardless, my words stand for this hat, I have a pretty deep love/hate relationship with it, love shines through most often though.
Full disclosure, I test and review some products for GORE-TEX. This beanie has been with me on countless winter climbing trips, several 14ers, and around town on cold days. I have never had cold ears while wearing it! The hat does a great job of blocking the wind which helps keep the warmth next to your head. That also means that it can sometimes be hard to hear your partner, especially if they're soft spoken. The hat fits great under a hood and under a helmet (the picture shows both). It also fits well around my head; some other beanies I have can get a little loose and sloppy, but this one fits snugly all the time. Highly recommended!
I have never found a warmer or more comfortable winter hat. Wore it on a nine-day trek of Kilimanjaro. Very soft interior lining, which feels supremely comfortable in comparison to most other wind-blocking hats I've worn. Very effective against the wind. Only down side is that because it is so windproof, it blocks a lot of sound as well, so it's harder to hear while wearing. That's a very small shortcoming for an otherwise FANTASTIC hat.