I grind whole wheat - however, in order to get fine flour, it will need to be ground 7-8 times and sifted in-between30 second grinding sessions.
The grinder works fine but there is no way I can put 2500g of product in there - it cuts out after 5 seconds with too much content.
I fill it about 1/3, grind 10 seconds move the drum back and forth to mix up the content for further grind - do this 3-4 times, sift - repeat until you have the fine grade of flour you need.
Wheat berries that are ground for 30 seconds (at 10 second intervals without removing/sifting) will be a coarse grind that I use to add to whole wheat or heavier sourdough breads.
the plate where the electrical cord plugs into the grinder seems very unstable as it moves and "gives way" to pressure when plugging in the cord - I believe this could be manufactured more stable - if feels like the plastic surrounding will break or crack every time I attach the cord.
For the price, I'd say this is actually a good product.
The picture I included is store bought AP flour on the left and the ground wheat berries - ground3 x for 10 seconds without removing from grinder - grind receptacle was moved up/down between grinds to "shuffle" contents between grinds.
We have also used this to grind coffee - this worked great for coffee.
Gordoon 
Rich 
