I replaced it, and the new one became intermittent and failed again within a year (reading was 600 something, and I have no idea how long it was dead before I got it). It was one of those LCD types that's embedded into the tach. I left the tach with failed meter and added a mechanical type that's been reliable.

Looking back it's just not important. The only use I have for it is to calculate accurate average fuel consumption per hour.

As you noted for your own use, I too do far less than 100 hours per year so maintenance is an annual thing. I also have a vacuum gauge with a drag pointer on the fuel line, so I change filters when I start to see higher readings. Usually less than once a year.