I've been meaning to watch this for a while but it is very long so needed the time.
Anyway, I have and I can really recommend it. I loved it.
And maybe the last chance to see Pacino, De Niro and Joe Pesci acting their socks off.
They used some sort of anti ageing camera work and I have to say, it was really effective given De Niro went from something like 90 to 20 in the film. Not once did I think, oh he looks wrong in this scene, but maybe I'm easily peased 
The film was very atmospheric showing America in the 50s, 60s, 70s etc... and the music was brilliant.
Just worth a watch 