Well, you can't say the polygon's are perfect, but I liked the graphics in the DS version very much. I'll always prefer this style to something that we had, for example in Xenosaga Episode I. I don't mean to say those graphics were bad, but I don't think the "realistic"-manga look (as opposed to super deformed) looks good in CG. I mean, on some occassions when you could see a close-up of Shion's face, she would show no emotion at all. Even in some dramatic scenes. The characters looked like they were baloons.
Anyway, the DS version guarantees, IMHO, the ultimate FFIV experience. The voice acting is fair, the new scenes are great... It' superb!