No brainer, Mobicool FR40 especially if you are heading across the channel for the summer, probably overkill for a British summer but you never know, miracles can happen.
There is only one gas cartridge operated fridge on the market AFAIK, it's a 3 way, LPG/240v AC mains/12v DC, Dometic Absorption type: https://www.dometic.com/en-gb/uk/products/food-and-beverage/portable-coolboxes/electric-coolboxes/dometic-combicool-acx-40-g-_-31768
They are fine for what they are, but have to some extent been superseded by more modern tech 12v/240v compressor fridges (but with NO gas power option, and at a much higher cost!), which are much more efficient at cooling and use far less power (you cannot run a Absorption type fridge from a 12v leisure battery, or vehicle battery without the engine running, it draws far too much current and will kill the battery dead in only a few hours), on gas, it will roughly use a cartridge a day. Absorption type fridges can't really cope with ambient temps above 25C, so UK fine, but southern Europe is pushing your luck, also inside a tent can get very hot on even a UK sunny day, so fridge won't cope unless in a well ventilated porch area.
We've got both a gas cartridge and a gas cylinder/regulator type adsorption fridge, so know them well, but also know their limitations, they are great so long as you don't expect too much from them. No direct experience of compressor types, but they get great praise from owners.
Yep Monty, we got our first portable compressor fridge back in 2008, a very lucky find for £150 brand new in the box, Waeco CF 25, fantastic little fridge but was always going to be a compromise due to the size.
In 2013 we added the Mobicool C40 to our kit, being mains only we ended up carting both fridges with us down to Frejus.
Not a problem with the trailer, but due to a change in company car policy, we had to leave the Mobicool C40 at home last year.
I am now considering the Mobicool FR40 as a replacement for both, as taking a trailer seems to be of the radar for the forceable.
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