Hadn't heard of the Jawhorse before, but it looks like a takeoff of the Black and Decker Workmate.
My dad bought a workmate many years ago, and due to being a workaholic and having a big bad ass workbench in our old garage, it kind of sat and deteriorated. Wednesday I noticed it, removed the plywood/particle board tops and replaced them with pressure treated two by sixes, drilled the holes for the pegs, and knocked the major rust off with the wire wheel. This thing is really handy, I may take it for my own...