Great idea simply because of how you make it work.
There are a few threads on here "about the work arounds needed" to make such a fridge function versus the purchase of a purpose built $900-1500 DC Compressor Fridge in the upright style.
But of course, replacement 3 Ways are the same cost of not more.
I know because I started one thread & was helped with a lot of answers & both negatives & positives.
How long have you been doing this??
Do you run a air curculating fan over the block or anywhere in the fridge?
What is your fridge temperature? throughout the day?*
What is the typical outside temperatures?*
I highly recommend these SENSORPUSH BLUETOOTH UNITS, even if you only purchase one - never any need to open a door & check a thermometer, all the info arrives via Bluetooth on your phone & you can track historical data by the minute, hour, day, month, etc.
Do you ever run the fridge on DC when you are driving?
What sort of Battery Bank do you have?
I assume you are not interested in adding solar?
Is its a budget issue for you or is it a question of need versus cost but it is a big cost to add solar just to have your refridgerated food safe.
Do you always camp with Shorepower every night?
If you cannot find Shorepower, what do you do?
Do you have a Generator?
Once again, its a fantastic idea!