as CBR954 SAYS... throttle response is faster. I don't know if its torque or inertia, but smoothness off the line may suffer, and smoothness while riding at low rpms, depends on your riding style. If you get off the line fast anyways, you'l probably like it. If you keep the revs up all the time anyways, you'll like it.
I just naturally downshift at about 3500 rpm, I like to keep the motor spinning.
IF you slip the clutch and ride a lot below 4000 rpm, you'll like it less or not at all.