Joe has some good points, I never used Expo or rates until I was flying for about a year then I started to play with them to find out what they did and if I like them or needed them. A lot depends on my planes how I set them up. All of my planes are now High Performance stunt planes so I set up both rates and expo on them all. I have been doing it for a while so I pretty much know what I like. I start at -45% expo and go up from there as needed/wanted but only on my ailerons and elevators and a +35% on my throttle with zero on rudder. I'm using a Futaba radio so the - minus. Depending on the plane I may end up with -65% expo. Another pilot may find {will find} my starting points way off for them but this works for me. I know this would freak out other pilots but anyone that fly's my planes love them. These starting points took a lot of time for me to figure them out.