Not sure this would qualify as a 'recommendation', more like a snap review. I bought the Wonder Mill about two years ago. Wife has pulled away from gluten and I along with it for the usual health reasons. We still make some whole wheat, sourdough leavened loaves now and again. We only have run Palouse brand hard wheat berries through it. The literature clearly states a limitation on 'oily' or 'moist' grains, but non-wheat seed products are apparently all right; corn, amaranth, etc. It comes off the shelf about once a month when a couple of cups of AP flour are needed and the other grain contenders just don't have the oomph of a good slug of gluten.
Otherwise, it does a commendable job on them, makes a slightly courser grind on the "bread" setting then I would expect in comparison to store-bought bread flour, but it works. The product comes out disconcertingly hot, despite the instructions and ad propaganda stating that it will "Grind 100 lbs. an hour" "for 10 hours without overheating." Define 'overheating.' The output is very warm to the touch, but I never put a thermometer to it. I'm guessing in the +90ºF range. You'll want hearing protection if you're going to run it more than a few minutes.
Cleans easily, breaks down (except for the actual business parts) into smooth, cleanable parts. It leaves me wondering what moldy, savory bits are sleeping in the actual guts of it. I just run a half cup of berries and toss the first output.
Feels good to know it's up in the pantry storage, ready for duty, better than needing and not having. In retrospect, I might have chosen a manual/external drive motor brand.
Hope this helps.