We already committed to Kinetico so changing brands is not an option. It does have a WOW feature I think. For drinking water, I am getting an RO faucet either from Kinetico or Waterstone. But I also want to get filtered water in the wall mounted pot filler. There are no RO rated pot filler faucet I could find.

Also I do not have an ice maker so that is not an issue. So it is just RO --> drinking faucet and RO --> Pot filler. The question is how to do the latter.

RO water will eat up the metal in any commercially available pot fillers. Plus if the water sits a while and isn't used, it runs the risk of developing bacterial growth in it because there is no longer any chlorine in the water to keep it from doing so.

Not sure the pot-filler option would be much of a convenience anyway. I have had two Kinetico K5W's at different locations for about two years. At 65psi line-pressure, the flow-rate from the tank is faster than previous air-tank unit but still not faucet-fast.....about 1.2 gpm. Holding tank holds 2.7 gallons and refills from empty in a little less than an hour. I am not aware of a larger WOW tank alternative being available.

I fill small pans at the sink from the RO spigot. Large pans I place on the stove empty and fill via transfer from a pitcher. If I know I'm going to have several-gallon need, I fill some pitchers in advance so I'm never stuck with an empty tank.

Agree with others about only using lines/fittings/fixtures designed for RO water.

Our RO solution is two really nice squarish Rubbermaid jugs under the sink and we work off them and refill as necessary.

The only RO-compatible pot fillers I've seen are made by Waterstone ~$1100. You also need food grade plastic tubing for the entire run from the RO tank to the faucet inlet.