This is pretty hard. I think I'd probably choose >10k mainly because the second option would make interactions with people pretty awkward. Being able to know all the details of someone's private life would make things a lot easier if you're looking to manipulate someone, but probably a lot harder if you're trying to bond with that person.
And while I could always just not use the power, that's what I tell myself every time I discover some overpowered strategy in a game. So I know exactly how that would go.
Ginhyun
http://i.imgur.com/t7G7uoU.gif