I'm not going to comment here on the concept, the design of the cards or the book; I haven't used them enough to experience any meaningful results. I'm only going to review the quality of the cards, which is terrible.
I'm very used to handling all types of cards - playing, Tarot and others - and these are just about the worst I've come across. The instructions tell you to fan the cards and select one from each category, but this is practically impossible because they stick together. Shuffling is completely out of the question. The only way I've found to pick a random card is to spread out all the cards from one category on a table - and because the cards are unnecessarily large you need a lot of table space just for one category. Even then it takes quite a while because the cards stick together.
As I don't have a large table available when I see clients I won't be able to use these cards for their intended purpose.
By the way, as I'm slightly colour blind, I also find it hard to distinguish between the blue and purple backed cards without looking at the central icon.