Useful for nukes from 68 until 72+, when it is outclassed by Errant/Mahatma Houppelande, Igqira/Genie Weskit, and certain Royal Redingote Augments. Decent Convert piece, though.
A very cute HP/MP boost, additional Conserve MP, and, when paired with other pieces of the set, some amount of Magic Accuracy as well. A decent piece at best for the low-level BLM, RDM's Convert, and BLUs and SCHs for instances in which the skill from their AF is superfluous (not often).
It is worth mentioning that of the plethora of mage bodies that outclass this, even Yigit Gomlek has 5 Magic Attack Bonus...