i done 58k in my tdci focus which was slightly modded to 128 bhp and 222 lb/ft with a smf in the whole time, never had one problem, clutch was smooth, quiet and i drove that car hard all the time. the cranks will not break thats a load of tosh to me i would say the concentric slave cylinder is not running true to the grooves on the pressure plate finger causing a pulsing through the clutch pedal, my current st170 does this and it drive me barmy