I studied with this book as well as CDs that are to be bought separately Objective IELTS Advanced Audio CDs: Advanced
for my IELTS exam, and achieved overall band score of 8: 9 for Reading, 8,5 for Listening, 7 for Speaking and 6,5 for Writing.
Therefore from my personal experience I can say that this set (book and CDs) is excellent for those who already are in upper-intermediate level and are prepared to make use of this book for achieving high score. I did not dream I could get 9 in one of the sections! Actually, after working with this book doing the actual exam seemed extremely easy.
My lowest mark was for writing, but there the book can not be blamed. This is just the week point of self-study method - you need a teacher to tell you what you are doing wrong.