I think this book is the best for beginners. After studying just 1st chapter, I've decided to register in German school in London to improve my studies.. So, I bought 12 hours and when I had studied 8 hours in the school, the school didn't had covered half chapter.
I've started with private lesson and my german teacher likes this book as well. So, if you really have time to study this book, do exercises and listen CD, it will help you a lot. There're a plenty of vocabulary, explanation and exercises. I'm quite happy with this book