I used Malibu C Color Prepare on a friend's hair. Her hair was in terrible condition. It was extremely porous from being bleached from dark to blonde repeatedly, and she decided she wanted to go copper. After previously using Malibu C on my own hair, I saw the Color Prepare packet and wanted to try it to see the outcome affect it would have on her hair. AMAZING! I could not believe how fantastic it covered and the shine it put in her hair, it looked incredible. After three weeks she washes her hair every other day and it has still kept a lot of colour. Color Prepare really does extend the vibrancy. I'll be using it every time I use copper or red colours! I love and recommend Color Prepare to everyone.