Dubbed all the way. If I stick to watching subtitled, I'd miss some great voice acting like in Hellsing.
Also, I can't IMAGINE Outlaw Star being nearly as funny without the timing that dubbing gives. Some lines are only funny spontaneously; I can't imagine Fred being as funny if I was reading it. Subtitling makes it feel, on the whole, more static, which is okay with some things. With hyperactive shows like Outlaw Star, though, it makes it feel a little funny.
Also, lip syncing isn't a problem in anime. If I was to watch Crouching Tiger, Hidden Dragon, however, I would have to go subtitled. Really, to be honest, for anime the voice acting isn't that good (at least in comparison to a regular movie). Basically, the higher budget of the movie I'm watching, the more I'll consider subtitling.