I've been using it for 2-3 months now. This is my second time buying it. Just ordered my third one. I've seen significant changes to the tone and brightness of my skin. As I like to be under the sun when I was younger, freckles came knocking on my door. With this serum, my freckles actually faded. As being said that Vitamin C are drying to the skin, this is not drying compared to other vitamin C serum. I have sensitive, combination skin. Another thing to note is that this serum although consistency seems thick, it is not sticky and it doesn't break me out. Another plus point there.