This book is good for stimulating some ideas, but not useful for practical application in most zones. It uses the Sunset Zones, and most of the gardens in this book are suitable for milder zones.
The photography is excellent, as are the explanations on how to read the designs. The designs themselves are a bit of a disappointment, as, for example, there may be full sun and full shade plants in the same bed.
This book can be a useful source for obtaining ideas to achieve a certain look.