It really depends on the anime. If its something that ive watched a long time ago, I will defintly choose dub over sub. (examples: fma, dragonball, yu yu hakusho, pokemon, digimon, and yugioh)
Anything new that i watch usually has the dub lagging behind the subbed version or the dub is plain ehh, so i watch them subbed.
Overall i choose subbed but i believe dubbed can sometimes match or even surpas the subbed in the right circumstances.