Thanks for finding the article. It doesn't mention anything about crowns not matching natural teeth after brushing. I think I will pass on this and continue to use the more familiar baking soda now and then. No one scary looking back at me from the mirror.
There's always a gimmick to sell more stuff. A certain electric toothbrush now has a water-pick flowing from it to floss with water while brushing. I have seen the infomercials. I don't think it would be that effective.