Depends on the plane. I have 40% expo dialed on for my ailerons on the Decathlon, same for elevator and 30 % on the rudder. I try to read up on the planes flght characteristics as much as I can before set up. If a few reviews say that it's a "twitchy" flyer, then I'll dial in more expo. Most of the guys at the field will start at 30% expo across the board and adjust accordingly after the first couple of flights. There are those that say, expo is the easy way out, but it's a good feature and I will use it to my advantage to assist with keeping gravity at bay