Subs will be always better than micro-transactions.
With subs, companies know how much income they'll get, so they can plan forward updates (or expansions).
With micro-transactions it's hard (or impossible) to know when the income will be high or low, therefore it's hard to update a game with an irregular economy, ending up with a contentless game. That's why some F2P games are just boring, low quality and contentless.