I bought this book as a fan of judge dredd, and although i do enjoy rpg'ing every now and again, i find the D20 system fairly tedious and not as usable as others, such as warhammer's D100 system.
As a dredd fan this book does deliver, with detailed descriptions of the big meg, and the characters that live in it. it offers explanations of justice department, and what all the different sections do.
Other things to note for gamers is the sheer amount of characters that can be played, especially for those reversing the roles and playing as 'law breakers'.
The main downside to this was that the whole feeling of despair and depression of the citizens that is portrayed brilliantly in the comics seems a bit lacking in this.
Also randomly at the end of the book the first 30 or so pages are printed again in my copy. thankfully all the pages that are supposed to be there still are.