I would not say good, it is just decent. Its best nature is Adamant. Seriously, its best stat is the attack stat, while its worst one is like a tie between Sp.Atk, Sp.Def and Speed. OK, speed is a bit needed to outspeed some little thing. Special Defense is needed because otherwise, some unpredicted special moves may KO it down. And Sp.atk is useless on it.
Now, if it is for Machamp, then the speed is the worst stat so any speed boosting nature would be useless. If you feel tired of catching again and again, then go ahead with a Jolly nature. Otherwise, hunt for the Adamant one.