The above listed are good. Once Upon a Time In America is supposed to be good as well. Deniro is in it. I haven't got to watch it yet.
For the record, no matter what anyone says, Scarface is not a mafia movie. At least not in the sense of the likes of Goodfellas, Godfather, and Casino. A good movie yes, but it's about the Cuban drug cartel. Common misconception made is the simply because Pacino is in it, that it is about the Italian mafia.