I originally had pink hair but once it washed out I wanted to go lilac so when that washed out I could tone it with a silver shampoo to make it grey/silver. I researched heaps and found out that using the Violet (and diluting it with conditioner instead of paying for the lilac Lilac that manic panic provides and using the whole tub all at once) meant that I could keep re-dying my hair once it washed out without having to keep spending $25 every few weeks. I've had the same tub of violet for about 2 months now and its great.
Downsides! if your hair is not 100% perfectly blonde all over then it is quite patchy, also when it washes out I found to my horror that the hair that shapes my face started turning electric blue and bright green......... it was unpleasant and my hairdresser was baffled and thought I dyed it all these different colours.
Also this is an ORGANIC colour, I learnt the hard way when I went to servilles and they turned my entire head mint green because it reacted with the chemicals in whatever they put in my hair and its been damaged ever since :( they couldn't really fix it and I ended up dying it lilac again..
p.s they don't test on animals :)
I love dying my hair assorted bright colours from blue to pink red and everywhere in between, and when I found a local shop stocked Manic Panic I was right in there buying their Atomic Turquoise. I started with bleached hair and put the colour in not expecting much of a change due to having used bad semis in the past. I slept with it in and in the morning when I washed it out I couldn't believe the colour, it was the most incredible light and bright blue. Even after a few washes the colour stayed. I have also used their purple and pink dyes and have always been impressed. No itchy or damaged scalp, no patchiness, and no dull colours. Thoroughly impressed. Currently have Purple Haze fading in my hair, started off really bright but still looks incredible as it fades to a lilac shade, still getting compliments :)
Tips: Always start with bone-dry hair and leave the dye in overnight for maximum colour. If you are looking to make your hair the brightest it can be, only use the dye on white hair no matter how long the bleaching process is. Don't wash your hair with any shampoo or conditioner for the first week to help the colour really soak in and stay for the longest possible time.