Idk abt that. I have a mb1000 and its holding up really good being I bought it used. I'm in and out of it all day my drawers are loaded heavy and have had not a single problem with it. No its not krl quality but works just fine for me. And I work at a truck shop so not the best enviroment. Mabey just the newer mac boxes are splitting or welds breaking? Mine seems to be made really well. My dad has the mb9100 9200 combo and turned wrenches for close to 30 years. Not a thing wrong with that box either. I had a krl so I know my tech 1000 isn't up to par with it but its still d damn good box. And not sure about any of the others but mine has holes for a third caster set.
