i us hard well water and just like token said keep the ph right i would think that it would be better then bottled water its untuched but then i have never tryed bottled water so what do i know
I've always heard from hippis that rain water is the best water to use, Not sure if it really does help, but when ever it rains i put out a blow to gather it.
invest in some ozarka 5 gallon bottles also as they will help you stock pile water. a good RO filter can make 15-50 gallons of water a day depending on quality desired