I've been lucky enough that my favorite series' have had good dubs. It is kind of cool hearing the Japanese voice actors, who ususally sound pretty into their roles. But dubs are more convenient and more accurate depending on the setting of the story.
But I just can't stand these "purist" otakus who completely ignore dubs like they were the plague. Recently I let a friend of mine from work borrow my volumes of Hellsing Ultimate, which has some of the best and accurate English dubs I've ever heard. But then she gives them back to me saying that her boyfriend downloaded the series, and when I asked if it was at least the English dub, she said how the guy hated dubs and got the subbed versions instead.
To quote comedian Jim Norton, "I wanted to bite his nose off, and spit it back in his face."