Is storing photo gear in a portable cooler acceptable?

I have been thinking about getting a cooler box as a means to put my photo gear in them. I have concerns about heat and was previously advised against putting anything in the car's trunk or glove box because of the heat. There are some large sized coolers that I am considering.

Is this a good idea? Another advantage is that it would look inconspicuous.

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Never buy version 1.0 of anything.