I am one of those who rarely drink the water from my tank. It is nothing to do with the quality of my tank, but everything to do with the quality of various sources of tap water. Even in my stick house, I rarely if ever drank water straight from the tap.
I bought a 2.5 gallon Brita water container with a spigot to fill my glass or tea pot for my coffee. I take water from the tap of the RV (or stick house before I went full time) and fill the Brita container, the 2.5 gallons generally gives me enough drinking cooking water for several days and I cannot tell it from bottled water. If I plan on some extended dry camping I usually buy a couple 2.5 gallon containers of bottled water, more to save my tank water for washing dishes a short shower and flushing the toilet.
When I got my small 5th wheel, I dumped some bleach in the water system and cleaned it thoroughly and I can honestly say that when I filled in Montana with good clean clear water the water tasted fine right out of the tap. But being on the road full time, means hooking up to many various water sources and some have good water and others have bad tasting water....at one site this winter the smell was so bad I pumped the tank empty at the first opportunity and bleached and cleaned the system again.
It is a habit I have grown used to and it works for me....my next RV will have a "whole house" 3 stage filter system and it will be a none issue, but that is a couple years away.
I always travel with at least a 1/2 tank of water in the tank and if planning on boondocking then I leave with it full.
Everyone has different idiosyncrasy's and mine is the water I drink!
Jim