I will never mount a vice to a fixed bench again after using a pedestal vice on a moveable steel base at my buddy's shop. It gets moved frequently as various jobs have different needs and quite often the workpiece is large or awkward. often the work needs to be painted, ground, cleaned or heated with the torch. something that you might not want around other projects on the workbench. The portable pedestal could employ a bracket for temporarily attaching to the bench when the extra weight is needed for the high leverage work