If you need something warm, but not too warm, this piece is almost the best I’ve come across. Synthetics like Helly Hansen thermal ¼ zip tops are too warm for >8C. Other’s smell to high heaven. I’ve worn icebreaker merino for a while but they smell after a day and trap salt and don’t deal with with temperature changes. They also don’t dry too well. I wore this for 3 days hiking, in 12-20C. It didn’t smell. It dries quickly and comes out of a wash almost dry. More importantly, I wasn’t overheating or cold with a light mid layer. My only, but major , criticism is the zip is really uncomfortable unless undone or done up. It hurts as it digs into your chest. A simple baffle, like you find on icebreaker tech ¼ zips would solve that problem. So it’s 4 rather than 5 stars. I don’t care how good the material is, if it’s uncomfortable it’s not going to be as inviting. Maybe it’s because I have a broad chest. But the solution is so simple and should be standard on an otherwise excellent piece of kit.