....they use ~3 gallons to outlet every 1 gallon of filtered water.
Filter sets cost ~$40 and need replacement 2x a year. So, on top of tripling my water use for stuff from the kitchen sink (much of which is not used for drinking, but rinsing/cleaning), it's $80 in filters to change annually.
I suppose I could line a separate tap off for the filtered water....
But I think the cost for that water would be about the same (or more) as refilling 5 gallon jugs at $1.25 each from Sprouts grocery stores. I don't think I go thru enough in a year to make the hassle and cost worth it. I'll have to track how many 5 gallon jugs I refill over a year. I think it's ~10-12. I don't mind having the 5 gallon jug stand in the corner to fill the coffeemaker in the AM....
Worth looking into, though, as a kitchen remodel is 'on the radar', and I can upgrade the sink with an extra tap hole for a filtered tap, if it makes sense.