I like the idea but not the design.
The cable appears to be wrapped around a central shaft.
Lock fails the moment after you turn to walk away and walla. At best the mechanism finds a home and catches. The jolt however might do more damage than that which would have been caused when your stuff hits the ground/car/dog/kid/etc.
I couldn't trust it.
I was watching the video they have of a person raising and lowering the unit as well as the installation instructions. I do believe it has a locking mechanism such that that cables would not lower if the lock was released or not latched in some way once the load was raised.
I do think that the load could be misbalanced though given a possible slight tilt b/c of the cable design from a central point as you say. If all 4 pulleys were independently mounted to the ceiling joists, that would be a different story.
