When I still had the big shop, had 2 Bend Pak lifts, both with wheel sets and the rolling crossing beams... They're better then 20 years old now and still there doing there job!!!! My favorite thing about the 4 posts is that when you weren't using them, you could roll them out of the way and use them for storage!!!! BTW, never did roll them with a car on them.... As Mike mentioned it was a bit too scary for me to roll one of them around with a car sitting up in the air!!!!!