I know this was recommended on here a while ago and people raved about it but said it's v hard to get in the UK.
If you want to try it (and are in London), go to Precious About Make-up in Shepherd's Bush, where the totally lovely people will match the colour for you AND sell you a generous sized sample bottle for £1.
Can't recommend them enough, they were just so nice. She tried three shades on me before we found the one that worked best, gave me loads of advice on how to apply it, and admired my shoes. 
It's a professional make-up artists' shop but they sell to the public too. (And I don't work for them, I promise.)