[microgamer2vs2]

I switch off. If a show has a good dub that's readily available (Funimation YouTube channel / Hulu), I'll watch it. I like being able to enjoy the animation as opposed to reading the subs and trying to enjoy the animation with the corner of my eye. Some dubs do too much localization, or just plain suck, so I opt out for subs then.

For example, I warched the first episode of xxxHolic dubbed first. Watanuki's voice just didn't seem right to me, so I tried the subs. The voices sounded more fitting for the characters. The repetition of words just sounds more natural in East Asian languages (mostly in reference to Maru & Moro, but Watanuki sometimes too). Additionally, they localized/adapted one of the parts where they were talking about multiple readings of Kanji, so I felt they took out some of the meaning in that part.

Good dubs I've watched:
-Baccano! - Story itself takes place in America, so English makes more sense for the series. The cast for the dub did very well with the various mob accents as well (the japanese dub may have had various accents too, but obviously it's easier for most Americans to distinguish between accents in English).
-Haruhi - The cast itself was pretty high-profile to begin with. They kept a lot of Japanese cultural references in as well, such as moe and the fact that Kyon refers to the girls by their last names. Moreover, these references don't sound out of place at all. My only nitpick is that "God Knows..." in English pales in comparison to Japanese.
-The rest of the good dubs I've watched: Any Miyazaki movie, FMA, Code Geass, Hellsing, Cowboy Bebop, Lucky Star, etc.

Avoid the Higurashi dub like the plague (When They Cry).