I have both the Cosmic 20 and Cosmic 40, and I'm very pleased with both. I generally take the 40 if the forecast lows are around 40 or more, and the 20 if they're less than 40. I've used the 20 without problems down to around 5, with heavy baselayer and light puffy. They're well made and durable. They're supposedly "hydrophobic" down, and I've never had an issue but have never gotten them more than damp.

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