Fantastic book I would totally recommend it for those who are preparing themselves for the CPE Exam.
In my case the experience I had with this book was great, I taught multiple differences and ways of using certain words that I wasn't aware of. For example, in my 20-something years as an English speaker and learner (as a Second Language), I never realized the difference between"Specially" and "Especially".
If you still don't know the difference, or maybe you do. I still recommend you at least check the index to see if something catches your attention