My bend pack has a tendency to sway a bit when the vehicle is raised up high and you put a bunch of side pressure on it. It kind of sways back and forth which is a little unnerving. I should note that it is not fastened to the floor, it is freestanding. But it is designed for that. I have a wheel kit so I can move it around. Also the safety latches to keep the car from falling if a cable breaks are each operated by an individual air cylinder, which is controlled by a single air switch. I have had problems when lowering it where one of the safety latches does not release all the way and then the vehicle starts coming down on three posts but not the other and goes out of level. I have to pay really close attention to make sure that doesn't happen or else it could collapse. There is no way for the operator to know if all the safety latch is released except to begin lowering the vehicle and see if it comes down level.
When I looked at the backyard buddy, The vertical legs were square box tubes. The carriage rode up and down on tubes that fit tightly around the legs. I had them raise it up and I pushed on the side of it and it seemed like it is more stable against sway than the band pack that has three sided legs and internal sliders for the carriage. And the backyard buddy had a mechanical linkage going to each safety latch so that one of them could not stick without the operator feeling it on the control lever.