Review (4/5): Doesn't fade but bleach is rough
I have been using bright hair colors for about 18 years. In the past I used Manic Panic and it faded - this stuff does NOT fade very quickly at all! I dyed my hair purple in October 2011 and it was still there nine months later! I bleached it and it STILL stayed, except it turned pink. This color will show through even if you dye over it, so be sure you want that color!!
I currently have white hair with blue and pink on the top. The pink is still vibrant and the blue is very dark.
Two words of caution:
The bleach is rough. Really really rough. Not too bad on the hair but very bad on the skin. It makes my whole head burn. Other bleach kits do not do this and I do not have sensitive skin. It does not, however, seem to do damage to the skin. No redness or anything. It just hurts till you wash it off.
The second thing is that you will think this is all washing out. For the first five or six washes, you'll see a LOT of color in the sink. If part of your hair is still white or natural color, protect it the first few washes - coat all the hair except the colored portions by rubbing in conditioner while the hair is dry. That way, when you wash, you won't get the color residue on the other hair.
I give this product four stars simply because of the bleach - the color itself is great. I have used purple, blue, and pink.