Well, there are advantages to both styles of coats. There is no clear answer about which type of material is best for your backup backpacking coat. Here I will quickly outline the pros and cons of both so you can make a clear decision.
While the down is the most expensive and lightweight it might not be for everyone. There are a few give and takes that come with each material. So what are the benefits of down?
A synthetic coat will inevitably be less expensive than a puffy down, but what will you have to give up if you opt for PrimaLoft (Patagonia) or even a Thinsulate synthetic insulation.
Nope, and there likely won’t be for quite some time. Once man made synthetics become lighter and more durable the race will be much closer. As it stands now there is really no way to tell if you need a down or synthetic. Generally, sometimes a down is best and other times a synthetic.
Since there is no clear winner in this race you will have to make a judgment call. Personally for most very cold weather situations I will opt for my Patagonia down sweater. However if it is possible that it might rain I would go with a synthetic such as the Patagonia nanopuff. On those days where you just want a super light backup coat, I will pretty much always have a Patagonia ultralight down shirt in a small pocket. These downs are so lightweight and pack up so small they rarely are ever even noticed in your pack. They are also quite water resistant and dry out fast for a down. They come with a stuff sack and literally pack up to the size of a softball! The links above are affiliate links, but I really do stand behind these choices. There are obviously a lot of jackets on the market to choose from, so enjoy your search. I hope I have provided some sort of insight!
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