Depends. We've gone down the "better" cooler route after camping for only four days this summer when it was very hot. Our old Coleman couldn't keep cold. Had to drive into town each day to get two bags of ice. Even then we had to move things around the cooler. The stuff on top wasn't keeping cold.Heck 3 days at most, a regular old igloo will work with just a block of ice.
A better cooler can hold more stuff than the cheap one even if the inside dimensions are the same because it requires less ice.
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