You can do it either way provided you store the RV in a spot that is level when not in use. I don't know of any real "downside" of either method since there are no moving parts in the fridge. I've had some RVs that the fridge ran all during the summer and others that I turn off and on only when needed. My CURRENT fridge I turn off when not in use and the reason is that it takes only about four hours to get completely cold. Some models can take as much as 24 hours and that would be a good argument for leaving them run (if you tend to be a bit spontaneous as I have been). Never wanted to delay a trip while waiting for the fridge to cool :)