Used these boxes to store books that we plan to resell next school season. You only assemble the boxes you need the rest remain flat until ready to fill (thus easy storage yet available when needed.) I like the uniformity and I can easily mark the contents on the outside of the box. And the price was right! Because they are cardboard they are not great for stacking heavy items.
The size worked well - having a "bad" back meant not overloading boxes. The size was large enough to get several items packed but not too big that you felt you would overload it so as not to waste the space inside.