I dont think Tapia was particularly good against southpaws. If Gerry just let's his hands go, I think he outboxes Tapia. Tapia might just outwill him though.
Both of these guys seem poison for eachother, which is why I like the match up. Tapia would definitely be out-fought during exchanges (who wouldn't?), but he'd out-work Penalosa and he was such a well rounded, quick, tidy out-boxer that he'd have the movement required to really bother Gerry. I don't think Penalosa presents the same issues Ayala did. I'd take Tapia to win by close, probably controversial decision.