Wildcard:
But I haven't played yet. My favorite genre to Roleplay is Superhero and I'm wondering if anyone has tried this system with Superhero games, and if yes, did it go well?
I gamemastered Superworld for years and it worked extremely well, till I wrecked my game by converting it to Hero system and then to other systems when that proved too crunchy for my players and myself.
Superworld is lean, fast, and easy to learn, gamemaster, and play. You will probably like it, your players will probably learn it easily and like it, and it does a great job of giving you the kind of super action that happens in the Wild Cards books. The Superworld books are all cheap at DriveThruRPG. So far, so good.
The down side is that Superworld is severely limited. For example, there are no vehicle rules. You can have helicopter piloting skill, but in game mechanic terms there is nothing to pilot. The villain jumps into his getaway vehicle, and the gamemaster just has to say that he gets away or that he doesn't. It's the same with laboratories. You can have percentage skill rolls in sciences, but the laboratory you are using is pure gamemaster imagination. And so on.
My advice is to think seriously about the limits of the game before you begin, and either accept them once and for all or go with a system that covers what you need. I would never try to change systems in mid-campaign again.