I use it for hiking. Either compared with a vest for "warmer" temps around 10DegC or as a standard baselayer for when it gets freezing. It does a great job at keeping you warm and the kind of cut/seams its made of (iE Raglan sleves or a continious piece of fabric on the sides along your armpits and along the sleeves) makes this piece really really comfortable to wear.

I’ve been running since the 70’s and have tried to keep up with at least some technical running gear to keep me comfortable under most conditions. But I also don’t like spending a lot of money. I relented after seeing reviews of this item and purchased it at the sale price. It was still the most expensive non-show item in my running drawers. I’m glad I did. I have run in this several times already and it has become my go-to baselayer. It’s comfortable (no itch), temperature adjustable (seems to keep me warmer when it’s cold and cooler when it’s warm), and the long zip-front allows me to control my running environment even further. Highly recommended to the to those who might be hesitant to spend over $100 for a top. Size medium fits me well; I’m 5’9” and about 155 pounds.