Last month we ordered an Edgestar 63 quart portable fridge/freezer. We have used it on one trip down through eastern Oregon, then over to Eugene. The fridge/freezer worked perfectly. It was 100 degrees in Prineville, and the cooler stayed at 38 degrees. It hold a lot of stuff as there is no need for ice. It runs on 110 volts, or 12 volts. We did run it down to 6 degrees below zero to test, no problems.
The bad news is that it's north of $500.00. We're retired, do a lot of traveling, and for us it's worth the investment. I would have bought this years ago if I had known how well they work.
There are several threads here on the forum that pertain to Edgestar if you search for that term. Maybe Edge Star too.