I really don't think you can make generalizations about a guy being a bust or not based on body type. Most of what determines if a player is a bust or not takes place between the ears. Ajinca was a bust, but the next guy that looks like that might not be. Drummond looked like a sure fire bust coming out but he is doing pretty good. Every one of these guys is like buying a lotto ticket, you might hit you might not.
Most of what i hear about Gobert says he doesn't look like an NBA player right now. Still wouldn't mind taking a chance on him though esp if we have multiple picks and he goes somewhere in the 10-20 range which is where I think he will end up.