I buy one of the Platinum versions of Optic White, which are less abrasive than many other toothpastes (including non-whitening varieties). You can google toothpaste abrasiveness ratings if you're really curious...there are lots of credible sources offering this information. Anyway, I notice a difference in my teeth within 1-2 days of using the Optic White line, usually by the 3rd brushing. It definitely makes my teeth look whiter and gets rid of any surface stains that made my teeth look dull and dingy throughout the day. My baseline color is very white already, however, due to ongoing whitening with professional products. Using Optic White just lets the whiteness of my teeth show, if that makes sense, because it gets rid of normal daily "wear and tear" better than other toothpastes. It really makes my teeth pop and look like that ultra-white movie star smile. Without it, my teeth can look very blah. I tend to only use this in the AM and if needed during the day though, because I have to use a prescription toothpaste at night (for a medical reason, not related to my whitening regimen). I took off one lippy because the flavor is pretty ho-hum. I've repurchased several times, and will do so in the future.