I've never seen these type of scales before and don't think I would recomment them either.
I would highly recommend purchasing a good used set of Intercomp E-Z Weigh or Longacre scales. Rebco's are OK too, just not my favorite. You can purchase a good used set for around $500-600 and these scales display weights & percentages of all four wheels at once along with left/right, front/rear, total weight & diagnol weight/percentages.
Much faster and easier to use and I've seen quite a few good used sets for sale the past couple of months. Maybe my buddy Jim #17 has some more to sell?
Just my two cents!