I have only been using this for 5 days but already can see a difference. I am normally quite skeptical of products making an instant improvement but the Radiance Serum has proved me wrong. My skin has a definite glow about it and I have stopped using my tinted moisturiser. This product has exceeded my expectations as my skin looks and feels wow. Very impressed - I will be making sure I don't run out of this glow in a bottle.