It is very messy! [SEP] I got this product a few days ago and have been using it twice a day since receiving it. I got it as a rebate in exchange for leaving a review.  So to start off I'm going to say that it is very messy!!! I had to clean my sink after each use, not just rinse it down the drain but actually getting the all purpose spray out and wiping it out of my sink. This stuff gets everywhere! it got on my shirt while I was brushing and well that stain didn't come out. I won't blame the product because its probably this way with all charcoal powders and I could have been more careful. I was actually very delighted with the flavor! In my opinion it tastes really good! bonus points to them for that. As far as whitening goes....I'm not quite sure this is even whitening my teeth? I've taken before and after pictures and haven't seen a difference besides the fact that it really leaves my teeth smooth! I think this product is great for cleaning the teeth, As for whitening though id say I haven't seen a difference and I've been using twice a day for four days. I will continue to use this product for probably a month because I've seen some reviews saying results take a while. I will update with results