Get it Jarrod....As you know I deliver auto parts to almost one hundred repair shops in my valley and almost of them have these lifts...some have two posts some have the four,some have both.Keep in mind these are pros that depend on their equipment to work & last.Most of them have the extra hydraulic lifts(one front,one rear)under the car so they can lift it up off of the ramps and free the wheels...I've seen 'em work and they are very handy.If I had the space I'd have one for sure.Nothing beats standing up beside a wheel or axle to do a brake job,there'll be no more bending over..
Oh,one more thing...the hydraulic lifts under the car are on slides so you can move 'em backwards and forwards so you can fit any car or truck.
I think these are powered by an electric motor/hydraulic pump system...no doubt 220v.