The picture(s) of the 60" workbench harbor freight shows looks to be fine. The only thing I would install different is a 3/4" plywood top.
I had a workbench "similar" to this one 20 years of so ago... too much give in the metal legs, by the time I got done securing & re-enforcing that thing - I could had built one twice the size & strength.
I built a bench similar to the one show here;
4x4 legs (you could use 2x4's also), I split a 4x8 sheet of 3/4" plywood and that makes the top & bottom shelves. I tacked on the top of the plywood with a piece of 1/4" or 3/16" MFD board (smooth side up), so when it gets trashed... just remove it and place another cover piece on and your good to go.
Has worked very in my reloading shop for over 10 years now.