I bought the Workmate II portable workbench back in 1989, and it held up well for almost twenty years, until I left it on the back porch for a few days and it got wet due to blowing rain.  (Blowing rain is not the friend of the particle-board top.)  On the hunt for a replacement workbench, I came across a really nice one, the Walko.

It comes in two models, the Walko-3 and the Walko-4 — the numbers stand for the number of vertical aluminum rails in the frame.  At first glance the Walkos look similar to most workbenches, almost like a sawhorse with two horizontal shelves, but with these you can adjust the height of your work surface by moving the shelves up and down the side rails.