To me, it doesn't matter which version I listen to, its personal preference. (I am also assuming AoT, sorry if I'm wrong) I prefer the dub over sub for several personal gripes I had for in the sub (personal opinion, not forcing it on you, reader):
For most of the series, Mikasa sounded like she had a lack of emotion. She lacked character even though she was one of my favorites.
Names were a gripe from the get-go. Most names in the series were Western, specifically European. On a personal lvl, I used to know an Eren, Armin, and Hannes. They were my European friend's brothers and uncle. So I was caught off guard and it took some getting used to.
To me, this is obviously targeted at Westerners. Erwin, Levi, Hannes, Annie, etc, these are all western names, its very hard for North American or European English speakers to screw this up unlike a name like say Tsunade, Itachi, or Jiraiya. Also, Western media such as comics, films, etc, are usually focused on some form realism, like AoT. So from the first episode I felt like a Cowboy Bebop-like experiment was taking place and it definitely succeed. Thus it made the sub awkward to me.