Iron Man was always my favorite of the group, and I think Robert Downey Jr. put in a great performance here, but not as good as in the original Iron Man. I don't feel he went full Tony Stark; he was toned down, had
to be toned down, because otherwise he would have stolen the spotlight from the rest of cast. It was still the second best portrayal the film, but he only truly shines when he can be the star of the show.
No, the best performance of the night was the Hulk, of all people. Forget Ed Norton, forget Eric Banna, Mark Ruffalo was perfect in every. Single. Way. I can't describe my favorite scene, because I would not do it justice (Drake, the part after Bruce Banner makes his reappearance), but I literally catapulted myself out of my seat.
Fracking amazing is an understatement. "I'm always angry." Just, gah.