I have a couple RO units that have been filtering my water for 8-10 years. Trouble free and costs nothing to operate, I just change the filters every year or so. I have a distiller too, but don't use it anymore. They use a lot of electricity. It takes a lot of power to convert a gallon of water to steam and back to water.
You can use a UV filter. Maybe not quite as reassuring as a distiller, but it helps.
UV filter won't do jack squat for Fluoride and heavy metals. Berkey gravity filters with a Fluoride filter add-on are a good middle ground and very cheap to run.
I have a well. My water is not fluorinated. A UV filter works wonders for me. If it's a good RO system heavy metals shouldn't be a problem in the first place and it will already have a fluoride specific filter. Distillers and UV filters are extras. As well as alkaline stabilizing filters and post carbon filters.
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