I read about a bench here on NAT a couple of years ago with NO vertical support legs. I liked that idea. We have one bench with legs & one without. The "without" is much easier to work around & when you drop something, you don't need to get a flashlight & broom. It'll be right there & not hiding under anything. Re. "strength", I'd say you could park a tractor on our bench. We used a laminate wood for the top. A very tight bench. Our supports are braced against the foundation wall...they won't move.

Open this link to my photo album page & you'll see a bunch of photos of the bench under construction.

http://imageevent.com/lukowphotos/workbenchnewshop