Good concept, and just having the option is an overall positive for the game, but seems like a clunky execution to me.
Would have been simpler & more intuitive to use if the auras had been integrated into the tailor. Could have avoided the redundant inventory bag & tacked on buttons as well as the c-store multi-pack with a half-dozen pieces for each aura with useless parts that now have to be stored indefinitely. Would be the same price for the c-store aura unlock, same account-wide use as a costume unlock, less annoyance for the end-user, plus I could preview them through the costume creator rather than guessing how it will look on my toon.