I like mine linear, for all types of flying but especially F3A where good throttle control is essential to presenting a nice flight. I only use a throttle curve to obtain this. ie 1/2 power really is 1/2 power etc.

Some people mix a flat spot in the throttle curve so that it looks like an "S" shape. People have done this in F3A to get a cruise control type of thing and also in 3D where the flat spot is at the throttle setting needed to hover. In the hover you therefore get much finer control of power. I personally dont think it makes much difference.

Angus