I built me sawbench wide, and low enough my knee can rest o a board placed on it. It's narrow enough that I can straddle it, so I can sit on any board I am working on, but wide enough to be comfortable. I have a gap down the centre lengthwise for ripping, and drilling. I also have dog holes in the top so I can hold birds in place. The feet actually make a shelf so I can support a board on end to work on it on one end.
My saw horses, on the other hand, are made out of metal, too high and narrow to support a board on, I can't put my knee on the bird to cut, as it's too high, and I need two of them. I usually use them to hold a board so that I can sit down.
i realize there is hyperbole here, but there it is.
Paul