The water you use makes no difference whatsoever.If I'm not mistaken I think he said he used established rocks with fresh water for only a day. That's pretty brazen and gutsy if you asked me.
Aside from the skill, if you real quality, established live rock is used it is nothing more than a tank transfer. Not saying growth and color will be amazing from day one. (no one will). But it's not exactly risky if skill and quality rock is on hand.