I have this book as well.
How good the book is depends on what you are looking for. It's very good for showing the finished details of a build of the Andrea Miniatures Type VIIC model. On the other hand, if you are interested in the prototype/real Type VIIC, I would point you to a couple of other books:
Vom Original zum Modell: Uboottyp VII C by Fritz Köhl
Type VIIC U-boats by Robert C. Stern