Well, you have to consider some things before you use this in your deck. If you're running a grass deck with mostly weaknesses to fire, then what decks are there to worry about in your meta? If Charizard is big, sure, run Metapod. If there is a substantial lack of Charizard, then it's not the best idea; it's just taking up space in the deck.
On the other hand, if it's in a Yanmega Prime deck, it is probably worth it to play Metapod, since LuxChomp is in almost every meta to some extent.
So it all depends. My meta has absolutely no Charizard, so I would opt to not run Metapod in a Jumpluff/Jumplume/VilePluff deck if I did have one.