The Coffee & Magic Verdict
My Royal Dream makes much more sense to us as an experience than as a simple purchase.
Our youngest is still very much at the princess-dress age, so the idea of choosing the look, having the hair and make-up done and turning it into a proper occasion is exactly the sort of thing that could become a huge memory for her.
It is expensive, so we would only do it if the child was genuinely excited by the whole transformation rather than just wanting another dress. For the right child, though, this is the sort of Disney splurge that can feel worth it long after the holiday.