I bought this after reading the reviews on hair. I am growing into my silvers and have stopped colouring my hair, but with that comes the colour fade from previous colourings, and for me that's a lot of yellow/brassy tones too.
Purple shampoos were becoming quite drying on my hair so I was in search of something to help tone my hair while the colour grows out.
I have a pixie cut - so the instructions and video's I watched would make application really messy for me, so I got a spray bottle and added few drops to that, and applied it that way. It works really well - you've just got to watch you don't spray your scalp too much or you'll be looking fairly purple - especially if you have fine hair like me - the mist makes its way through the hair easily.
Application aside, once the hair is dried, the brassy tones had really faded and I was looking more ash toned, which is fantastic. My silvers are really 'silver' and glitter like too! Unlike the shampoos my hair was left soft and not dry at all. It gradually washes out - and the good news is if you're too heavy handed you can get the excess out with one or two washes. I can get about 4-5 washes before I want to put the product in again.
The bottle will last ages doing the application with the spray bottle so I'm really happy with the results. I'll be sticking with this one through my journey of going grey.