I've found the book really useful for my collecting focus on the famous Washington/Franklin postage stamps issues 1908 - 1923 using Scott numbering. It covers all important facts to know about the stamp variants and especially ways how to easily authenticate and distinguish each particular issue. I suppose, the main goal is to warn collectors against faked more rare stamps produced from their more common variants. The book contains more detailed typology of 2 cents and 3 cents stamps and recommendations how to distinguish similar types. I found also useful the end-notes especially: "Detection of Design Alterations" and "Determination of Printing Methods". I would appreciate more up-to-date typeset and color pictures especially in those cases when the precise color shade is the factor of differentiation. I also expected at least general lists of the most typical printing flaws.
This is absolutely a GREAT BOOK. However I only give it 3 stars due to the fact that this book is only worth the original price of $60.00 . The information is also available in the scot specialized catalog and the Martin Armstrong books. This book is not worth the $150 to $250 that some of these philatelic want to be's think that it is worth. DO NOT PAY THAT AMOUNT. This book is available at $60 to $75 if you keep an eye out.