Hyperformat provided all the formatting parameters you'd ever want
to control,
ran in console (text) mode and wasn't exactly easy on the eyes.
Also, it used all kinds of low-level tricks to squeeze the most out of
the FDC. In short, it was a tool for people who really knew what they
were doing.
PumpUp was a conscious deviation from this approach: It still provided lots of useful formatting parameters, but presented them in a nicer GEM user interface. Also, it used operating system APIs to format the disks - but often with an unusual twist. For example, using PumpUp you could produce very fast formats, i.e. formats which allowed to load programs or data from the disk much faster. It also provided support for high-density and overclocked FDCs, but always used OS services to accomplish this.
And the best of all its features: Its name .-)