It depends on your starting point. Are you highlighting it with bleach first?
I like the Mydentity range and have used the 8DL with a dash of 3MV on a client who wanted a pinky blue tone to her 100% white hair.
Red colours tend fade more quickly especially on pre-lightened hair so I might be inclined to go slightly darker initially and explain to the client about the natural fade off. It really depends on your clients hair and their colour expectations.