This book combines Neal French's "Potter's Directory of Shape and Form" along with Constant & Ogden's "Potter's Palette", along with some pages of additional decoration photos. By this I mean that the exact pages of those other books are what this book consists of. Thus, it is a better buy than either of those other books.
Both of them are useful resources. To get an idea of what this book contains, look at the reviews for those books. The result is a very handy & informative book, but I can imagine a book which is even more comprehensive, which is why I'm giving only 4 stars.
p.s. By the way, I spent a few moments paging through this book looking for any mention of Constant & Ogden, the authors of the Potter's Palette, but I couldn't find any (if it is there, it is obscure). How is it that they can publish this book under Neal French's name without any evident mention of the authors who produced half the book? I wonder what book the additional decoration pages came from?