I use the Vallejo
Model Colour royal purple (which I assume is very very simillar) extensively with my Dark Elves. And I couldn't find a good 'out of the pot' highlight colour. I mix VGC Bonewhite into the Royal Purple and it comes out great. I use varying ratios depending on the model etc. Give it a go and see how it looks.
Worth a note, I noticed that the wet paint is slightly brighter than that it looks like when it's dry.
Good luck. Post results