I replaced our 2-way fridge with the 10.7 cu. ft. Everchill 12V compressor refrigerator about 3 months ago. It pulls right around 55 watts when it runs, and it runs maybe 60%-80% of the time, depending on ambient temperature. That works out to around 800 to 1000 watt hours per day, so the .69kWh per day for the smaller fridge sounds about right.
I ran a dedicated 10-gauge wire for power to minimize voltage drop. A smaller wire might not be a safety hazard with these low amp draws, but voltage drop can affect the performance if it’s too small. Everchill gives recommendations for wire size in the installation instructions, based on length of run.
Regarding boondocking with a 12-volt fridge - as a fulltime boondocker, I can say it’s definitely possible as long as you have an adequate solar set-up (or you don’t mind running a generator). We have 1440 watts of solar panels and 600Ah of lithium batteries which handle the 12-volt fridge with no problem. I would say a system half that size would be adequate if you don’t have a lot of other “out-of-the-ordinary” electrical needs.
Overall, we are much happier with the 12-volt fridge, and highly recommend it. Temps are consistent, it’s quiet, and it’s roomier than our old Norcold N8X.