That's kind of like pitting a tiger against a baby, isn't it? Considering that Jayna was able to defeat Superman, the only possible way that the CMC could win is to somehow keep them from activating their powers to begin with. As much as hate to say it, this fight goes to... science. *gags*
The wonder twins vs the cutie mark crusaders... So... Two superheroes who can literally become anything versus 3 kids, only one of whom has any abilities above normal (sweetie belle can somewhat use magic) Yea, that's fair.