The colours last amazingly well. One of my old ladies fancied the pink, at xmas, so I slapped some in foils. I didn't even pre-lighten, just straight over her grey, as she on wanted it temporarily. It is still there! I couldn't believe it. The blue and green are subject to fade and are prone to needing two applications. Also, if you don't get the pre-lighten light enough, it looks a bit muddy. So the can be a bit of pain when doing them on darker hair, as any yellow tone tends to interfere with the final result. I have some one with the red on my photos here and the orange, yellow and blue on my FB.