The torque it takes to spin the blower and pump remains the same, and you still have the same number of belts, one for the engine-to-generator and one for the motor-to-blower, I can't see how there would be a difference.
One benefit I see is the motor-to-generator belts see a fairly constant load rather than the torque pulses created by the blower, and you don't have to contend with the complex harmonics set up when trying to drive the blower through a long flexy shaft.