Millenium Steel Box 2

Needed to tidy up my studio, and decided to get boxes for separate effects units. Ordered Millenium Steel boxes, 2U and 3U. 3U box is as expected, good quality and rigid even for heavier equipment, and several can be stacked on top of each other. But the 2U boxes were very different: steel material is thinner and this, together with the construction of the box, how the metal is bent, makes this 2U box inferior compared to 3U box, and not suitable for anything heavy and/or and stacking. Also, they are slightly narrower than the 3U boxes, so they look like they were made by different manufacturer? Decided to return all 2U boxes and get more 3U boxes instead.