In the thirty years since its release, it has been nearly unanimous across the globe that there is no other film about prison that can be any better than The Shawshank Redemption (it has sat at the top of the Top 250 IMDB list since I was in High School.)
I am not arguing against that (it is one of the very few movies you can find any dislikers for). I bring it up only because it gives a warm feeling of sorts that you would not get in many movies (let alone one about prison). That feeling does not come around often, and no other film about prison has passed that on to me since. Enter Sing Sing.
Nothing else to say 