It's okay, but a little too general in places. It's also written for a British audience, so a lot of the diagrams and techniques are reversed from what you would encounter in the USA and elsewhere. It's a good refresher, but they should have spent more time on the advanced topics.
Received this book as a new associate of the Institute of Advanced Motorists. The advanced system seems very simplistic but trying to implement it on the road just from reading the book is not realistic. Looking forward to my observed drives.