Hey which of these three is best for the purest fluoride free water with the CHEAPEST cost? Considering the water waste of RO, power use of distiller, etc.

Are there any COUNTERTOP RO systems that work well? Im willing to pay around 400 if it's worth it. I don't want to drill a a hole on the drain pipe under the sink for an under counter RO system because i have an old copper pipe...

thanks a lot guys