I've only had this product for a couple of weeks, and I've been pretty faithful about using this product. So to let you know, so far, I've experienced disappointing results. I am giving this product the benefit of the doubt by saying I noticed only 1 shade lighter results. I appreciate the ease of applying the material in the pen, but having to refrigerate the pens is not convenient, additionally the cause of this lower rating. I will update this review if I experience significant improvement in color.