Pete, I was talking to Allan Wardill ASRA's Opps Mgr and he mentioned to me that he believed many Americans put up with way too much stick shake. Allan has attended and flown as PIC in gyroplanes at Mentone many times.
Confession....I have a double slider and a tiny bit of play couple thou with the block inside the towers. I can literally make a tight circle with my thumb and forefinger around the grip, allowing 3mm-4mm gap and next to zero movement or anything amounting to stick shake. I am not using the pushrod ends with springs that Larry has on the Auroras.