I have found oil gauge is really not that important,I change my oil more than really needed but oil so cheap and check the dip stick often before every start up and make sure the idiot warning light is working and look under the engine for any kind of leak.
I find that a temperature gauge is more important and found that when motoring how important it it is if and when something clogs the strainer or maybe there is a problem with a leak can over heat and cause big problems and been boating many years and it is cooling related problems happen more and so I do a temp gauge at the helm and if I see that gauge is showing higher than normal than I know to check things out but that's just me and so far been working real good.
Nick