Armoury Chest

[Fantasia]

How else would you be able to tell the game you wanted to equip the job instead of the class? It's not redundant, it saves having to equip the soul crystal separately after changing class.

You can have 1 gear set for MRD and 1 gear set for WAR.
Only WAR would need the soul crystal, so you can place it directly into the WAR gear set.
It doesn't need to be placed on the armoury board if you're only using it in one gear set =)