Originally Posted by
Wolf Kanno
Eiko is better for not just having the better White Magic selection, but also having Dbl. White as her Trance mode which makes her pretty versatile and gives you dualcast Holy, which will trump anything Dagger can pull damage wise. None of this is helped by the fact that while Dagger certainly has the better summon selection in terms of raw damage, she doesn't really get access to it until Disc 3, which she spends half of in her traumatized state, meaning she really doesn't get super useful until Disc 4.
Course I use Quina as my healer/support character, so it really just comes down to playstyle.