I hadn't had much experience with cold weather backpacking until recently (I live in Hawaii) and picked this ether shirt up along with an Icebreaker bodyfit 260 base layer for when I was actually hiking. I couldn't be happier! This windshirt weighs next to nothing and cuts the chill wind out completely while still allowing enough heat to escape that it didnt become a sauna when my body heat rose. I alternated between putting the hood on which kept me about 10 degrees warmer when the wind was really blowing and taking it off when I was in the hollows and such. We took a few side spelunking trips from the main trail where we had to belly crawl though some pretty tight spaces and I just took off the windshirt, balled it up into its built in packing sleeve and stuck it in my pocket. I wasnt sure how well it would hold out against the constant scraping across the jagged cave floor. I strongly recommend this shirt!