Stila convertible colour? - think some are in the M & S sale Lipstick Queen (50%off in space NK sale right now)?
It's the pigment that you're paying for, generally. Personally I haven't found one as good as the high end ones for lasting. Blush isn't something I want to have to reapply, so it's one of the things I would spend on.
However I've heard good things about Sleek blushes, although not sure if they do cream/lip/cheek multiple style pots.