This mill is sturdy, but rather coarsely manufactured. If all you need is a coarse grind, it's a great bargain. As with many hand-crank items, I recommend a food-grade grease, like Lubriplate Food-grade grease, to reduce wear on the worm gear/shaft. There is a break-in period and system; you need to wear the burrs down, so they meet more closely, sharp edges are removed and metal bits worn off. I put a bunch of whole wheat through, from cracked to as fine as possible, multiple times, then pitched the wheat (contained metal). Then, ran rice through, coarse to finer, multiple times. I took it apart to examine the burrs and they were taking awhile to polish/wear down, so I added 1/2 TBS scouring powder to the rice meal and ran that through multiple times. After that, the unit was completely disassembled, washed, dried and re-lubed. Grinding more rice showed essentially no metal flakes. A magnet test found a little metal powder (less than half a millet seed's worth).

The output is likely too coarse for tortilla masa (from Nixtamal), but probably fine enough for polenta and tamales. I own an old Polish grinder, given to me used, and it's a similar design. However, the Polish burrs are very worn and produce a finer flour. I expect this mill will eventually do the same, but it may take many dozens of uses. I plan on using this to pre-grind Nixtamal, so it can be ground finer in another mill.
Update: 9/3/2017- I added a star since the mill was able to grind Nixtamal finely enough for tortillas, which came out excellent. A finer mill clogged up with the coarse, damp, ground corn, so I put the coarse Nixtamal back in the Estrella grinder. First pass through was set for coarse, necessary for whole corn (lime-treated/washed). Two more passes with the burrs tighter produced a finer masa than expected. Use the back of a wooden spoon or a chopstick to aid in getting the damp cornmeal into the worm gear, as the meal tends to cake and stick to the hopper a bit. Remember: the grinder was broken-in as described above. As the burrs wear down, the output becomes finer. You want to wear the burrs down and throw out the resulting rice,wheat, whatever, before you use the grinder for food. I'd give the grinder 5 stars if the burrs came pre-worn, broken-in.

We are very happy with this grinder. We grind our own peanut butter, and it is a replacement for another one that we gave away. These grinders are difficult to clean, but the peanut butter we get from it is worth the labor! It comes from our neighbors to the South, Mexico -and I thought all we sent down there was pollution and automotive! Anyway, they are our neighbors and I wish them well as I do our neighbors to the North, Canada.

My mom is happy with it but says the product was built a little better when she was younger. It ground the Lyme treated corn well but needs to be run through 2 times. Also the beautiful red paint is not painted on evenly and has a few unpainted patches. It only affects it Aesthetically .

Although the product showed up with some minor wear and tear on it I am very pleased. I did interact with the seller and they did reply fast. Although we never came to an understanding what happened (issues from shipping or before) I am pleased with the product and it performs as expected. Minus the couple flaws in it it exceeded my expectations.

The grinder is heavy cast iron except for the hopper, which is a little flimsy but functional. It grinds beautifully! The shipping box was beat to a pulp by the US Postal Service, and, as the contents were not well packed, the body of the grinder had a chip out of the paint, but everything else was just fine. It comes with no instructions for setup, but as long as you have any mechanical aptitude or a knack for puzzles, you can put it together easily enough. It grinds smooth, fast, and easy.