This has been brought up before and is always an excellent debate. A few years ago my vote was for Casino. But for about two years, I give the nod to Goodfellas. For me, it's a few things: the acting of Paul Sorvino is superb, the smaller characters like Morrie, Spider, Frenchie, et. al gives Goodfellas an added dimension and depth over Casino. Plus I like the flashback scenes with the younger Henry & Tommy. My favorite character is Jimmy Conway, portrayed wonderfully by DeNiro.

All that said, there's not much to dislike about Casino. There is less humor than in Goodfellas. Ginger is a character that the viewer grows to despise, whereas there is no such character in Goodfellas. I love the beginning hour of Casino, especially the scene where they catch the two guys cheating. I like the lesser characters like Gaggi, Frankie, and the casino boss played by Don Rickles.

I'd give both films 5 out of 5 stars.