Subtitles by far for me.
I think as with anything, the original, intended depictions are always far better.
Even though english is my first language, I always think that when I see things dubbed in english, the voices are just god awful and do more harm than good.
There's even been several times I've gone abroad, and flicking through the channels there I've come across certain english programmes, such as Friends in other languages, and their voices are just as god awful dubbed! I have a friend from eastern europe who started watching Friends in his own native language, and he thought it was horrendous. I introduced him to the original, english version (he was reluctant to watch it after how bad the dubbed version was), and he loves it!
But yeah I don't think it matters what language, dubbed programs/films/anime are always awful, or at least are never
as good as the originals. Not from everything that I've seen.
Sure, for some people subtitles might be hard to get used to at first, but after a couple of viewings you barely begin to notice them anymore.
Besides; seeing what 4kids did to One Piece when they dubbed that in english (OH GOD WHAT IS THIS THING?
), I firmly stand by that dubbing does more harm than good, in most cases.