Yes it depends on the plane as reneb said...
But you said your plane is sensitive. If this is a foamie or a wild 3D-machine I would suggest 40% expo on ailerons and rudder and 60% on elevator as the first attempt. In addition use dualrates on your first flights to avoid just snapping into ground before you have learned the behavior of the plane.
On really wild 3D`s it is not unusual to have 80% expo on the elevator and 50-80 on ailerons depending on what you like and what suits your flyinghabits
