It's pretty difficult to empathise with a game's tragic heroine when you're too busy wishing she'd just shut the hell up. Eternal Sonata's voice work is often so dismal it's laughable - consisting of tedious drivel and wooden acting (full of... really... odd... pauses) a boatload more irritating than even Blue Dragon. If you last up until the true opening credits, some 30 minutes into the game, CVG will come round your house and applaud you as you make your way down your driveway to work. Congratulations.
Dialogue is crucial. It can make a decent RPG exceptional, or it can make a great RPG, well, a little bit annoying. Here it's a fairly major blemish on an otherwise charming adventure. So, do yourself a favour and switch to the Japanese voice from the options menu before you even begin playing, and thank the CVG team later.