I have several benches and they are made of 2" lumber exclusively except for a shelf down across the legs. Even with that shelf below well loaded and a set of shelves abut 4 feet high sitting on the back of the top of the benches, against a wall, and also well-weighed down... there are times the back of the bench lifts up when one of my RCBS presses is put to a difficult job. My benches are also 24" x 48". I might have made them 30" or 32" wide if I had the space, but the basement room they are in is pretty small.