Wish i could help you Grandad ol' mate...but i cant really.
I bought a little domestic one--the same brand as my Waeco fridge...the reason i got that one, was i absolutely nailed the guy down on such a great price i had to take it...
And also because at the time, it was the only one that i could find that would run on 12V out the back of my car out bush...
Since then, i dont use it much, & ive only ever used it once out bush--just because i wanted to test it on 12V...
Watching with keen interest though,,,so hopefully you keep updates here as you progress through to a decision...
The man who knows everything, doesnt really know everything...he's just stopped learning...