I think it is worth it ,it does give you a good overview of some of the things to learn if you not that good at reading books.
Ignorance is larger price to pay than £15 for a dvd which cover most of the topics needed to pass the exam and remember the key terms. Is getting a low E or D grade worth trying to increase your chances of learning something new from a different source.
The audio and video help re enforce the key points to remember for the exam.
good luck and if it helps you share your views with other.
Good revision tool.