Very good take on Batman, focusing on the grittier side of his character, even before that style of comics has became as popular as it has today, clearly shows that The dark knight is human, and fighting people at 50 could prove a challenge.
The ideas of splinter Batman groups are great ideas, "the sons of batman" prove to be a way youths have risen up by the memory of Batman to combat the "mutants" although they're rather misguided, without Bats' they torch buildings to convey a message.
The way Bruce shows his guilt for the Jokers crimes because of his inabillity to break his rule (not to kill anyone) is a great climax towards the end of the story.
The series can also be found in a graphic novel form, where i first read it, which is a good way to get the story read without breaks...
As it provides a great insight into Batmans head, and it portrays what gotham could become without a hero, i'd give it about 4.5 out of 5, and i also agree with 'smile' It would make a great film.