Maokai vs rumble

I like rumble a lot more. Depends on the matchup.

Moakia

I play both, but I definitely like Rumble a lot more. They both play different roles though. Maokai is basically a tank and Rumble is often mistaken for one (I don't know why). They both have amazing teamfight potential, but Rumble is at his prime mid-game while Maokai (correct me if I'm wrong) is at his best late-game.

Rumble by a lot, but probably more my playstyle than a fact. Rumble is still helpful with his ult that can be game changing in team fights even if he gets a bit behind, Mao can't really say the same for any of his stuff.

Mao can scale well but he needs to break even at the very least to be as good where rumble can be behind a little and still turn a fight in his team's favor