I set up my GT:HD controller options so you use the triggers for the pedals and right stick for changing gear, but I found my fingers used to slip off the buttons because for some stupid reason they're convex rather than concave, as a trigger should be, so i've gone back to the buttons or stick, depending on whether or not i need precise control over the throttle or brakes for a while, such as drifting, in which case i use the stick. Otherwise my 'foot' is 'flat' to the 'floor' so I use the buttons.