In addition to being a nice nuking piece till 73, Its "Refresh" effect is invaluable.
Cheaper than Vermillion Cloak and Less work to obtain (And at an earlier level) than Sorcerer's Coat.
Although if you get a Sorcerer's Coat you might as well get rid of this thing.
Agreed, good piece that every BLM should consider getting, especially for the refresh as BLM need all the MP they can get. (Until you are able to wear Sorcerer's Cloak or Morrigan's Robe if you are able to get them.)
I personally use this most times on my BLM, and switch to Igqira Weskit only when I need that boost in damage, or for endgame.
As Leonidus said, the Refresh effect truly is invaluable.
If you are like the rest of the Black Mage World you probably still killing pets from 50~73 (Save Aby leaches) or your making a panda cry and actually level syncing still. So naturally you will love having this item to help keep your resists at the floor. The INT+4 helps the loss of your AF head, and the Refresh can be to die for.