I prefer the subs.
First of all - I'm learning Japanese so it helps to be surrounded by the language XD
Second - I like it because it's in it's original form. And also, with dubs, the conversations completely change. I mean, they could be completely serious in a Japanese version but in a dubbed version, they could be attempting to crack an extremely bad joke. Also, I've grown used to multi-tasking which includes reading the subtitles and watching what's happening :3
I only watch dubs if I'm watching anime with someone, such as my brother. I can name a fair amount of good anime dubs and decent English voice actors, but I prefer the Japanese seiyuus.
Also. Johnny Yong Bosch is a perfect example of a (wayyy more than) decent English voice actor, but Daisuke Ono is equally as good (Both played Itsuki Koizumi in the Haruhi Suzumiya series)