As regular readers of this travelogue are aware, I'm fairly skeptical of ballads, demanding to be impressed by great writing, great singing, or great arranging before letting any low-bpm romanticism past my rock-reared defences. So I was already listening to this with one eyebrow raised, as it were, from the very first notes.
It's not bad! Castro's found his own rather fine voice -- no longer shamelessly aping Luis Miguel, he's found his own tricks of intimacy -- and it's tastefully-arranged, with lovely acoustic guitar runs and actual piano instead of electric approximations, and a slow saunter of a bolero rhythm underpinning the whole thing. If it's not lyrically a knockout, well, it's a conventional romántico ballad. "Lo Mejor de Mí" means "the best of me," and the chorus is a complaint that he's given her his best, but it's not enough, she keeps hurting him and he doesn't deserve it.
But then I clicked over to Wikipedia to check up on any facts I needed to know, and saw that it was a cover of Rey Ruiz's 1991 original. And, well, I'm sorry, Cristian, but a danceable salsa ballad is always going to kick a self-important dirgey ballad all to hell. I know I'm something of a hypocrite here, because I love nothing more than a good wallow when I'm romantically rejected, but Ruiz's version, in which it can never get that bad as long as there's dancing and buddies you can do a call-and-response with, is infinitely more attractive to listen to.