I think it depends how you grip, or how you're used to gripping. The fk1+ used to cramp my hand as well, i tried it out after the FK2 and FK1 gave me cramping issues. My hands are 10cm wide, i noticed people with larger hands using FK2's without issue. It's more about grip preference and letting your hand adjust to the shape i think. So far this mouse has not given me any cramps, it seems to have more support for the pinky where the FK did not.