I think there are two main points why the "Oz" is dif then most of the other shows.
1)Like most HBO shows they show it all the good and the bad(very very bad)
2)The thing that made the show that intersting is that it never gets boring I mean new chars keep showing up and die or what not , I mean yes there are a few chars that are the main but not in every ep. I mean some ep u would beraly see bicher if u would even if he is one of the main char, they can focus on a char that really only came 2 the show and would prob die sooner then later how can a show like that get boring.
And yes i think killing said was... unesesery mainly because no1 care about the person who killed him, it wasnt like when said killed Adebisi thou that wasnt as exsting as i tought it will be :/. Any way if u havnt seen this show wait for reruns or download it cus if u wont u missed a very VERY good show, u just need the stomatch for it.