I've used these bins for past 4 years in an old drafting cabinet to organize all of my hold down hardware, small end mills, taps, etc. They are very tough and hold up great.
For my main hardware storage (screws, nails, bolts, etc), I recently bought 32 of the HF 20 bin storage cases, then built a rack to hold the cases. While I really like the HF cases, the largest bin size is about 3" x 4.3", which was a bit short for some of the contents (drill bits, long bolts) or when I had more of screws than would fit the bin.
After thinking about it, I went and took some of the left over Schaller bins from the drafting cabinet and was able to use them in the HF cases. The 3x6, 3x8, and 4x6 sizes added a lot of flexibility in my storage inside the cases!