Quote Originally Posted by Ultima Shadow
Vincent stands in backline and have sadness= He takes about 30% damage from all psychical attacks AND less damage from ALL attacks. His Death Gigas is godly in early game. He has very good magic defens and magic attack. While two of your partymembers slay with their limit, Vincent can stand back, heal (his magic is powerful) and survive (sadness+backrow+good magic defense= very hard to kill.)
He also has THE crappiest limit break in the game. It might be somewhat useful early on, but later his limits aren't worth it since he can't use materia.
Magic can be altered(magic plus materia and/or sources). Magic power's his sole benefit early-on(especially with healing), but later his lack of damage because of no good limit is just too much.

Fact: every other part of a character(defense, attack power, magic power, etc.) can be improved except one: limit breaks. Since Vincent has a sucky limit break, he's just not worth it. Especially since you can get the Magic Plus materia early on(very beginning of disc 2), and it's pretty easy to master.