We have a separate ice maker from the frig/freezer. In our boat use pattern found it much more important to have extra freezer space. Fortunately was easy to shut off the ice making and use it as a freezer.
Perhaps if your use pattern is mostly day trips with lots of people or you are on a large boat where space and electrical draw at anchor isn’t a concern they are a good addition. But for us and I think many it’s rare you need more than 2 trays of ice cubes in a day. Usually that when we have company and can buy ice or make ice a day before and store it in the Rtic. Find keeping some drinks in the frig, using stone for things like scotch, storing some alcohols in the freezer ( gin, vodka) makes ice needs lower.
For caught fish it’s dressed when caught then shortly eaten or rarely frozen as fillets. Think you never can have too much freezer capacity
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