My Hitec Eclipse 7 transmitter has both positive and negative exponential available. How do they differ? Do both of them soften the control throws near neutral? What kind of percentage do most 3D flyers use, or does it vary widely by model? I've seen some people recommend 60% on everything, and others recommend -15% on ailerons, -45% on elevator, and -30% on rudder.

Thanks,
Clay