Regarding 18Greens' query about types that require brakes to be set for spinning and aeros, to the best of my knowledge the rule is always to set the brakes off. Taking the Chipmunk again as an example: as you bring the brake lever back, you get progressively more braking as you deflect the rudder bar. Since you are now pushing against the hydraulic pressure, the rudder travel decreases. When the lever is fully back, you can't move the rudder at all!. This is clearly not desirable if recovering from a spin or trying to make coordinated manoeuvres during aerobatics.