VII was definatly the best, very convenient and most of them were
really good(eg. Omnislash, Highwind, Catastrophe)

VIII was very useful but risky which i liked

IX was awful it comes up at the most inappropriate times and it goes away at the end of the fight.
Everyone says that Zidane's Grand Lethal was soooo OMFG!!111!53092374kl;jdckl;fdej
but Lionheart and Omnislash actually did more the 9999.
Steiner sucked because he didn't so anything it was just increased attack
Garnet's and Amarant's sucked for the same reasons.
really the only good one was Kuja's and that's not to useful.

X's was kind of just an improvement to IX's but was still pretty boring.
maybe it's just cause I hated just about every aspect of FFX