I’ve worn at least 8-10 different brands of Merino over the years. I thought I had the best money could buy.....and I was wrong. The cold weather performance has yet to be tested, but my other (-33degrees, IceBreaker, SmartWool, Filson, and others) garments are very warm, so I can’t imagine Woolx isn’t at least as effective. The noticeable difference is the feel against your skin. I now have two different pieces and both are the most well made I’ve owned. And there is no contest when it comes to feeling soft against your skin and not itching. My -33 doesn’t itch.....but it doesn’t feel like Woolx. I spend way too much money on hunting gear and clothing, therefore I’ve sampled almost everything. I’m as impressed with Woolx as with any clothing I’ve ever worn. I will be buying more. Also customer service is spot on. Zero buyers remorse this time.