I'll happily sleep in a quilt down to around 20F. That is just called Fall here in Minnesota. I love being able to tuck the quilt around me the same way I do in my bed. For full on winter weather, we're talking below 0F here, I use a bag and I don't see that changing for me anytime soon.
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If I wouldn't eat it at home, why would I want to eat it on the trail?