DB,
"
I am not as convinced that "Motion" reduces "Sim Sickness".....as it is physically impossible to replicate actual felt sensation by means of the motion system.
The few times i got Sim Sick was upon flying the Sim immediately after lots of hours of flying the real helicopter within sometimes just hours of the getting into the Sim.
Your body gets confused when what you see visually does not comport with what you naturally feel during flight in those same situations. That is what got me....you do a steepish turn in the Sim and there are no G forces produced as in actual flight. The Sim may shift initially but then gradually reduces the input returning towards level as the turn continues....which is not the case in flight.