If you need definitive proof that "sticking with something" eventually yields great results, then you need look no further than this video of Edgar Cruz playing Queen's "Bohemian Rhapsody" on classical guitar.
I play guitar myself (all self-taught), but this is quite out of my league as far as current abilities go. So, even though I totally hate Edgar for his talent (that by far exceeds mine), I do really like the guy as well.
Not only is he extremely talented, he seems very personable, kind and down-to-earth. Methinks the world would do very well having more guys like him - even if he does make me look like a total chimp on guitar. Bastard! :P
Edgar Cruz - Bohemian Rhapsody