Flight, hands down. The thought of being able to go camping in Peru if the mood strikes me would be great. Plus it would be a great way to meet women. I think that they would be less creeped out by someone who can fly than somebody who can watch them shower if he wants to.
I’ve been asking this question to a lot of people. You get widely different results depending on the context. People are much more likely to choose flight when in groups. People are much more likely to choose invisibility when alone. I think this is because people are ashamed of wanting to be seen as perverts. Men are more likely to want to fly. In groups of two, usually one person will want to fly and one will choose invisibility. I suppose it’s because the second person feels compelled to choose the second option so that the group can talk about it.
A silly question: if you urinate when you’re invisible, is the stream visible?