I can't speak to the quality of Bean's regular bags but I have an older North Col bag from them. It is rated to -10 and I have been comfortable down to -15F. All the rest of the gear I have gotten from them has been the highest quality. It is not necessarily the lightest weight but well built and reasonablly priced for the quality.
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If I wouldn't eat it at home, why would I want to eat it on the trail?