The number one reason every wizard should have this item is because it contains an instant-casting self-buff spell. Melee are not the only ones who get hit with AE dispel, and rather than pay someone else to farm something for you (goblin skull earring), or doing a long, involved quest (coldain ring), you can do this very simple quest.
Also, like the Eye of Innoruuk, you don't have to cannibalize your stats to wear your buff item, as this has a decent intelligence modifier.