I read and studied this book when I was taking Advanced Inorganic Chemistry. I found it incredibly useful and helpful. To be honest, I used it more than I used my textbook. Not that the textbook was not well written, but because this book is so well organized and practical.
The book starts with symmetry, symmetry elements/operations and point groups. In the end of this chapter, you start to learn matrix representation of those operations and learn how to use character tables.
The second chapter gives very brief information on quantum mechanics. The authors really did great job to keep it as simple and useful for students. So, don't panic. You can easily understand this chapter as long as you are comfortable with calculus. On a side note, I should mention that EVERYONE should learn calculus.
The third chapter is about Vibrational Spectroscopy and the application of Group Theory. You can see how symmetry is used in spectroscopy. I promised to do some practice problems here on the blog and I am sorry I failed to do so. But, I will keep my word as soon as possible.
The next chapter is MO Theory and the last chapter is about Electronic Spectroscopy. I loved these two chapters because you can really learn how symmetry is used to interpret spectra and data. Textbooks have similar problems too. But, what makes this book special is that everything is explained in more detail and the practice and chapter problems are from REAL publications. I think this book really pushes you to read publications. You can see how EACH vibration of para-difluorobenzene is assigned to an orbital!
I think anyone who is interested in Inorganic Chemistry, Physical Chemistry and spectroscopy should read this book.