Smoother. In a late war German tank traverse was hydraulic and dependent on engine speed for speed of rotation. The gunner could only roughly lay the turret on target and had to make final adjustments by hand with the manual controls. This is due to the inability to fine control the rate of traverse with the hydraulic system. Hydraulics take a light touch (try operating heavy construction equipment some time) and can be jerky if you are heavy handed in their operation. They also don't respond instantly to changes in motion.
US vehicles had a variable speed electric traverse that allowed the gunner to both fast traverse onto a target then use low speed and fine control to lay the gun. This made for a much faster on target time that has been repeatedly documented in numerous histories. And, in tank engagements he who is on target first and firing first usually wins.