For conversation's sake, I spoke with my cousin and he advised that you can add a variable core kit to the 459 which basically allows for a looser center but doesn't give density adjustments. A user-adjustable density kit is available on the 469 balers, though. Reason being is the 46x balers are built substantially heavier and JD doesn't want folks cranking down on the 45x balers too much and tearing stuff up.