We headed out to
Berline-Icthyosaur State Park for an overnight. In spite of the altitude, it reached about 90F during our travel time and set-up afternoon. The last 15-20 miles are on a dirt road, and I had needed to do some interior clean-up when we arrived. No plugins, but bright sun for the Solar Panels. Upon arrival, the lettuce was frozen (but not the beer). We had been traveling with the supplied thermostat set to "6", and turned it back a bit (towards "5").
The OEM thermostat, following that adjustment, seems to have done a good job... but with no unfrozen lettuce for a further "test", and PID measurements taken only by hand , a couple of times... I can't say
exactly how much temperature variance occurred inside the fridge. But it seemed very tight - not reaching above 40F (SWAG) and definitely not freezing the remaining beer within the night.
Very pleased overall. With bright sun for the entire drive to camp (3-1/2 hours), my batteries arrived fully charged, and after the overnight it had fully recovered by some time before 2 PM. Maybe a long time before 2PM, but we were out touring, and didn't see exactly when that occurred. (Night time loads included my CPAP and the Fridge - lights were negligible, because they're LED.) I didn't try to take a current measurement.