If you are viewing this, I recommend trying it!
I was hesitant because of many reviews claiming it turns everything black, but it really isn't as bad as it was made out to be.  It works rather well and my teeth feel amazingly smooth and clean after using this and following with a traditional toothpaste brushing.  As far as it turning everything black, I believe if you are somewhat careful and just rinse everything (ie sink, toothbrush and teeth) I see no problem.  I also use the scoop and put it in my hand to transfer to the toothbrush, that way I can rinse my hand and it doesn't get everywhere.
Rating: 4 stars