This book helped me to gain an A*. It contains all the essential vocabulary in an effective revision format. However, the explanations of some of the more complex grammar left me needing more help. It also advises on exam technique, e.g. giving you examples of some succesful answers. Plus, it divides each of the sections into foundation and higher, making it easier to focus on weak points.
All in all it serves its purpose very well, and several of my friends have rated it very highly.
However, it does depend on how you revise, but I think this book caters for most methods.
Also, if you find listening and speaking(especially pronunciation) difficult, I recommend the version with the cassette, although I myself did not use it.