I personally don't own one of these grinders, so I borrowed one for the test. This first grinder took 25 minutes to grind one cup of wheat during the 1 cup test. I called another friend who also has one of these grinders and she told me her grinder was a lot faster than that. Using her grinder, I ground a cup of wheat in only 6 minutes.
So, what's this grinder good for? If you never plan on actually using it, but are keeping it in reserve for hard times, then maybe this grinder will fit your needs. It will grind wheat, however it will grind the wheat slowly. I expect that it could grind a lot of clean wheat before it wore out. But for those of you who only keep a grinder in reserve for hard times, the argument can be made that if your family ever does find hard times, you are going to want a grinder that can grind a large amount of flour fairly quickly.