I have a lot of acne scars and worried about dark spots a lot so I decided to give this a try since it was on sale for $9.99 and I am repurchasing this once it goes on sale again! I love it and it absorbed so well into the skin that it does not leave any sticky residue at all. I often hate ampoule /serum because it's too sticky sometimes but not this one. Whitening-wise, it does show some result but don't expect overnight miracle.