@Kind Soil, now I got to question, why " no liquid" ph source be used? That makes no sense whatever. Maybe you failed to be specific in this. So why not lemon juice, or vinegar, etc for organic ph adjustment? and some people HAVE to use RO water. If its been properly treated with calmag ( at a reduced ppm, I'm using 60 ppm for the kind soil ) and properly ph'd I see no logical reason for it to be a problem, unless your mix is lacking in certain trace minerals/elements. Tell you what, I'll send you a couple gallons of my tap water, you'll be horrified at what it does to your plants!
without a better explanation, it sounds like a sales pitch ( not saying it is, just how it sounds ). So Why would these crystals be better? its all the same after it dissolves..