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 didn’t 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 wasn’t sure how well it would hold out against the constant scraping across the jagged cave floor. I strongly recommend this shirt!

I live in Hawaii, and I bought this because I was going on 3 backpacking trips that were back to back in the winter up north USA and northern Italy. It was a bit of a gamble on which one to buy. I wasn't sure if it made sense to buy more layers instead of this one big weatherproof parka but I tell you what I stayed warm and dry the entire time and loved every bit of this jacket! The only thing I have to say that isn’t 100% positive is the pack size. I jam mine into a compression sack and it’s still bigger than my tent. For the Ultralite backpacker I would suggest doing a base layer, then an extremely lightweight down layer, and then adding a cheap disposable clear plastic emergency rain poncho (The kind you buy from Wal Mart) as this will be a much lighter alternative. If you are not an extreme ultralite backpacker then just buy this jacket for any really cold weather conditions.