I am a professional psychic and I find these cards very accurate, especially in the short term (the next two to six weeks after the reading). They are also excellent for Yes or No questions, with a little bit of interpretation.
However, I do agree with the reviewer who says that these cards are dangerous for the novice. If you are new to using oracles of any kind and want to learn cartomancy, don't start with these. Try Titania's Fortune Cards - an excellent, fresh interpretation of the Madame Lenormand method of fortunetelling that puts a more positive spin on a lot of the darker images. But these cards are great for more experienced readers who are looking to add a new dimension to their work.