Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Packs small, but terribly cold.

I like to sleep fairly cool. But I wore a base layer to bed and was freezing in the mid-40s. I've taken this bag several times and the experience has been the same. I have no idea how they can say it's 20 degrees. If I were climbing into this bag in 20 degree weather with no base layer, I would have real safety issues.Also, even if your core is warm, the foot of the bag is always cold. Always. Even if you wear snowboarding socks.It does pack small and light, so I give it credit for that. But I'd look elsewhere if you can.