I found dual audio not to be the awesome feature I always thought it would be. I thought the ideal would be to have the text in English and the voices in Japanese, but after actually experiencing it I'm not so sure anymore.
If you can understand a bit of Japanese (I usually understand about a third of the words and I know a lot of generic phrases) the text and the voices can cause some unexpected dissonance. I've come to believe video game translations are pretty liberal. It's not just the usual stuff like reworking puns, I think the translators make an effort to make it seem less 'Japanese'. Most people know about the famous examples in Phoenix Wright, like ramen becoming hamburgers. From my experience, that kind of stuff happens a lot in translated games.
It was very distracting to hear something and understand (or mostly understand) what's being said, but then also read something different at the same time. The English text and the Japanese voices don't gel well together. I found myself focusing on the differences between the two, which took me out of the game a little bit. Most recently I encountered this with the Atelier series and the Final Fantasy XV demo. Because of this, unless the translation is really literal, I prefer a good dub.
Anyone else experience this?