Silverone

For the new d20 hero systems i would recommend Mutants and Masterminds. Very fast paced fighting unlike Champions and a more consistent rules structure than the old Marvel Superhero game. The character creation is pretty simple but allows for almost any superhero build.

http://www.mutantsandmasterminds.com/

The game system has some flaws but really every one of them has something that has to be improved to some degree through house rules.