I have fair skin and this is the only product that helps with my dark circles. On my second tube after hopping from concealer to concealer for the last decade+.
This product works decently. Used underneath concealer as directed it does help my dark circles appear less and doesn't look cakey. It's no miracle though, the circles are definitely still visible. For effectiveness I'd give it 3 stars. The two star rating is because this has got to be the least value for money product I've ever come across and I'm saying that as someone who is well versed in high end and luxury cosmetics. You get a tiny amount for the price. I don't pile it on and even so, in two weeks I can tell it won't last much more than a month. To make matters worse, the packaging is such that there is going to be no way to access the full amount of the product. A squeeze tube would at least let you get to more of it. I buy a lot of cosmetics and this one is a total cheat. I will use what I have rather than return it, but I will never repurchase something that is such a rip off.
This product acts as a concealer and brightener for me. I love the way it glides on with no effort under the eyes. Not noticeably a makeup at work and does the job easily.