We have a 60l engel fridge (3c) only in the camper, but we also have a 92l DZ primus fridge/freezer (3c/-16c) split door in the back of the tug.
The 92l is a bit big but has the same foot print as the 65l so no more floor space than the smaller one and it means we have heaps of space even if we don't take the camper.
We have never run out of fridge/freezer space lol
The Primus and ones like it work differently to the Engel DZ'z in that it has the same amount of cooling lines in both sides, but uses a gas valve to divert the cold gas to the area when it's needed. Both sides are digitally temperature controlled A much better way of doing it , which I find works very well. You can also only run one side and turn the other side off if you want.
We use the F/F in the tug as the bar and freezer, drinks, mixers, ice and frozen foods. Ice cream is a bonus
In the camper fridge is milk, juices, veggies and other foods.
The freezer in the tug does cycle more but i find with 270Ah's of battery a 120w panel and bush bashing for a few hours most days the batteries stay topped up.
The fridge in the camper cycles a lot less, so the 210Ah's and a 160w panel the batteries last for ever.
We also carry a Honda Eu20i and 15amp/5amp(tug) 40amp(CT) chargers during winter or for shady spots long term.