Steve,
I too was impressed with Paul Sellers workbench. I came across his videos via Wranglerstar, who built Paul’s bench. In fact I am just about finished with mine. See attached pic. All I lack is installing the well board and installing the vise
It is very sturdy. I used all dimensional fir lumber. I plan on putting a 2x shelf across the bottom stretchers.
Good Luck with you build.
Bruce
Oklahoma