Caveat emptor? Of course! But, this test outperforms the many free flashcard exams. It also does a good job testing your actual knowledge. However, and here is the but, when it comes to the actual exam you need to know everything, there are no shortcuts. The IAPP exam is rigorous and merciless as it should be.
This test exam for the current price tag, you can't go wrong and is very good. It helped me a lot while prepping.