General rule is to set the gains as high as possible without causing oscillation. As Uri said, aileron and elevator values would usually be the same or very close but rudder could be very different.
If you have the gains too low the heli will feel 'loose' and wont hold it's orientation very well, for instance the tail would wander left or right. If you go too high you start to get oscillation/shaking as the gyro over-compensates.
The heli is easiest to fly when the gains are 'just right', neither too high or too low.