As previous posts have noted, an impact driver has much less "reverse kickback" than a standard drill/driver.
To me, this is a disadvantage when using it for the jacks. I use the feel of the reverse rotation of the drill/driver to gauge how much force I am putting on the jacks and when to stop. The impact driver does not offer the same feel and it's very easy to overextend the jacks and stress the frame.
Also, a drill/driver with a torque setting can be used to prevent overtightening of the jack.
Steve
