A Cambro says it loses 1 degree an hour. I'm not sure what kind of holding times you're looking for, but if you put piping hot food in a cambro, it'll be piping hot hours later unless you open and close it alot. The cold side I'm not as familar with, but I would think the same would apply. The blue ice wouldn't hurt. If nothing else, you can pre cool, or pre heat prior to putting foods in.
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