Great game, I really love multiplayer games, Couch coop/vs is my favorite type of games so I might be biased here.
Solid entry, player it with my bud and we had a lot of fun. If I could change one thing it would be to make the controls more intuitive. (ex. make up be the jump, down the stomp, right and left be direction changing and sliding). It would really help to be more accurate, as it is what is most difficult in this game, without changing the gameplay.