As a newcomer to the subject I found this a well written and apparently balanced approach to the subject. It shows an awareness of the stereotyped image of the inquisition but doesn't become obsessed with attacking or defending it. Instead it offers an overall survey, complete with helpful rather than cumbersome figures and an excellent use of colourful quotes.
Having presented this overall introduction it then goes on to describe how the stereotype has been produced over the decades. This works well as the final chapter - giving a background to Kamen's account and the image of the Inquisition but avoiding the 'for and against' argument dominating the book.