Usually when an actor calls a movie great, they're talking about one they're in. So, of course, you take it with a grain of salt. But surprisingly, Robert Downey Jr., of all people, said Guardians of the Galaxy is the best Marvel movie. And if he's willing to throw aside his ego that's as strong as Iron Man, we're willing to believe him.
"Galaxy in some ways is the best Marvel movie ever," Downey Jr. told the Toronto Sun. "We’re talking about how the Iron Mans and the Thors and the Captain Americas and the Avengers movies have afforded Marvel the opportunity to essentially take what was a third-tier, minor, kind of upstart bit of potential from one of their comic books series and say: 'Look!' It’s like you have a great quarterback, and his brother plays for another team, and then you say: 'Look, this is their second cousin and we think he has a great arm and he should start.' And then he goes and wins the Super Bowl!"
There you have it: Guardians of the Galaxy is unfuckwitable. Even with Iron Man as (in-house) competition.