You should definitely put it in your Mass Levitate. Since you're looking to only affect yourself, having up to 10 opportunities to proc is better than 1 opportunity. That said, if it came down to a single boss, and you have no other minions to proc off of, then single target would be optimal. But generally speaking, go PBAoE. And if you can, minimize the enhanced recharge in the power to better improve the proc performance per activation.
Makes sense. Looks like I'll put it in Mass Levitate. Thanks for the advice. :)