I was not impressed with the results of Stain Shield product. I noticed a very slight difference, so I cannot say the product didn't work at all, but most definitely NOT worth the high cost. I gave the product a 'fair' overall review, but definitely a poor 'value'. For what you get, I would say this is more along the lines of a $10 value. This is the one and only whitening product line I've tried, so the others may work better as that's what customer care seems to be suggesting. I'm just not so sure I want to invest another $40+ dollars....