I have one of these.. used to be way cheaper than YETI, especially if you can catch a sale.
It does hold ice for several days, but not sure about 4 days in 90deg.
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My biggest issue is for the large size of the cooler, there isn't much space inside.. It's all insulation/foam in the walls.
Perhaps somebody can create one using NASA aerogel. Bet that would be cheap /s
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