He looked average until the final round..... He was focused and did some really good work, but only for a round... I don't think it has anything to do with the southpaw or style of Quintana... Berto seems to have a hard time focusing himself in a fight and doing what he is able to do.... If he can get his head straight, he could be an elite fighter still.
He still doesn't look ready for the step up to the elite class, why not unify against Zavek first? wouldnt do him any harm, i think Floyd, Pac, Mosley and PW all beat him at the moment.