I used RO water in my cpap for a couple gallons, to less than stellar results.
It left a fine powder clinging to the tank.
It was probably processed from LOCAL water, and basically just FILTERED.
Our local water is very hard--osmosis does not remove dissolved minerals.
It just filters out particles (dirt, critters, etc)
It might also remove some odors, which might be worth it for some.
I just use home distilled--and let the bullfrog de-lime the distiller.
