Al and I have been discussing this also, with planning a future trip, so the comments here have been really interesting and some very helpful to our own situation. I particularly liked the tip of packing tomatoes in a supermarket cooler bag to stop them freezing, I would have quoted it and known who to thank, but I'm not sure how to do that, so thank you for the tip!
With all the comments of capacity and numbers of units being used on a trip, it was interesting to read that many restock fresh meat and veges all through their trip. This works well as long as you are travelling through highly populated areas. We had friends recently return from a trip inland and they were really shocked at the lack of fresh vegetables and fruit. Some prior research into the areas you are planning to travel through seems like a sensible thing to do. Something else that tends to surprise people is that in smaller places, the trading hours are limited and you can't just duck into the shop after 5pm or on a weekend.
One thing that no one has mentioned, or that I noticed at least, is their ability to lift fully-packed fridge/freezer units. I'm aware of this only because my dad - who is nearly 80 - is talking about selling off his bigger unit to buy two smaller ones that he can move around without causing a hernia or breaking his back. It's all well and good to travel with the larger units, but if you have to move them for some reason, can you do it? Just something else to consider.
At this point in time, I personally think two or three smaller units may be a good way to do an extended trip, if we have the room of course. I like knowing that if one unit doesn't work correctly that we don't lose all our cold food.
But it really is a personal choice, dependent upon what room you have and steady power supply, your dietary requirements, the length of stays outside of townships, and as in a case like my folks - the physical capabilities to move things around in camp when needed.
Just my thoughts
Jan
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