This has been my first and third experience with white strips. I tried Ollie's first, and liked the results. Then at a friend's suggestion tried Crest's version, which I felt caused some discomfort and did not markedly improve the Ollie's outcome. I returned to Ollie's and am seeing improvement again.

I only put four stars because I am not through with the whitening. I’m impressed so far and will continue to use the strips until I’m through. I tried a week first and then ordered two weeks more. I have very stained teeth first from taking an antibiotic in my teens that really yellowed my teeth and then drinking tea for decades. I’m optimistic when it comes to this product and have seen a very consistent whitening especially on my upper teeth. So far so good!