I'm thinking in terms of normal maneuvering as well as motion due to instability. The latter is probably more tiring as it would be present throughout most of a flight.
But for normal maneuvering, what are typical roll vs pitch vs yaw angular motions about an aircraft's CG? While these are directly perceptible by ones vestibular system, the linear motion produced by the product of the roll/pitch/yaw and the distance one is from the center of that motion is what produces those 'stomach-flipping' accelerations.
