I'm not sure if this was was posted somewhere or not, but from the screenshots and the demo I played at the store when your not in battle mode you can run around and fight, see, and avoid the monsters. (Pretty much like Star Ocean till the end of time). Can you move around like that while you summon an esper?

When you summon an esper, 2 of the other people in your team leave and are replaced with the summon. You control the summon like you would normally. But you can only control it for a certain amount of time then it disapears. If it dies before the timer runs out then it disapears aswell.