Why this book title specifies Britain in the title I don't know because virtually none of the photographs are taken in Britain. Most photographs were taken in Greece or other southern european countries so the photographs may not represent exactly what you're likely to see in Britain anyway.
One of the features of this book is supposed to be that the pictures, text and maps are all together for easy reference but in fact some species are carried over to the next page so the pictures may not actually be visible with the text. Could have been so much better if a little more thought had been given to the layout. One butterfly per page would have been much better.
I suppose it's difficult to show all the variations but the photographs are too incomplete to be a full guide. The butterflies are not shown with open and closed wings for both sexes nor are variations at different times of the year shown.
All in all it's not a book I would recommend for anyone who wants a single book to identify British butterflies from but it could be useful to complement a guide on British butterflies or if you want a guide for holidays in southern europe.
I wouldn't have been very pleased if I'd paid full price for this book but at a discounted price it's okay.