Despite the enticement to recieve a free tube in exchange for a positive review i will offer my experience, which i would have either way. This product is very expensive for what you get, The intial clicks left me wondering if anything was going to come out, and then i touched the tip, and subsequently my eye, which led me to a world of pain.
So anyways, after i came to terms that i basically paid 22$ for 1/4 a pen of product ive used it twice daily for 5 days with optic white toothpaste after and have seen no notable difference. The good news is i dont have any sensitivity which i was worried about, the bad news is its probably because of the ineffective formulation of this product. I stayed away from my normal staining products during my test period- and used it as directed.
I will go back to using 5 minute plus white with a q tip, its messier yea, but atleast it did something, and i don't have horribly yellow teeth or anything, but i am self conscious at the lack of bright whiteness. 0/0