Recommendations on home mills, please

So that is a pretty open ended question.  One option is an impact mill- like the Nutrimill -  they are very fast, though not necessarily the finest grind.

The next option is a stone or steel burr machine -  one stone is fixed , the other rotates and the distance between the two is adjustable to vary how coarse you are grinding.  Many here like the Komo, though the Mockmill is a similar design and has its followers.  Slower than an impact mill, but usually can get a finer milled flour,  though it depends on setting it just right.

The problem with faster output of a stone mill, that means either the stone must be bigger than the competitors or the stone must spin faster, which will normally mean the flour will come out hotter, and many believe that negatively impacts the nutritional value of the flour.    For ex. the Diamant has 5 1/4" burrs  diamant-grain-mill   other mills use stones that are 3 or 4 inches in diameter.

If you want the finest, it is hard to beat the Lee Household Flour mill - new versions are sold as Royal Lee lee-household-flour-mill/   used ones of the original model Lee show up from time to time on ebay - they don't use a rotating stone to adjust the fineness of the grind, so they can be set to grind very fine, though the downside is that they are slower than most.

Another thing to consider is do you want a very fine grind.  Some suggest it is helpful for some products like pasta, others suggest a coarser grind is better for pasta-  for bread, there is at least one study that says it is a bell curve, and as you get more fine, at a certain point it decreases openness of the crumb. 

If by greatest volume , you mean not how fast will it grind, but how long, then the best bet is a Retsel Mill Master - while their customer service is rated very poorly here, there is no real argument that it is a beast - a 1 /2 hp with an extremely over engineered gear reduction system, it should last forever.  Other machines that will last nearly as long, though turn the stones at a higher speed, include the All Grain allgrainmills, marathon, magic mill  - which i think are  only available used,   As a result of COVID,  supplies of the new mills have been spotty, and the price of the used mills have skyrocketed -  a check just now on ebay showed listings between  $250 and $300 for mills that probably would have sold for around $125 to $150 pre covid. 

I own a Mockmill 100 that I use daily or more. This thing is a work horse and the grind is extemely fine, especially after I double mill grains. I also use it to make rice flour, flax meal, grind random spices etc. If you are a tinkerer, it is really easy to open up to inspect/play with the inner workings (they made it this way deliberately, you don't even need tools to do so). I think it also has the best price of all the home mills.

You will probably want the Mockmill 200 or higher (the number indicates the grams of flour per minute it will mill) .If you have specific questions I'd be happy to answer them. If you want to see how well it mills flour, my latest blog post features a bread that is 100% fresh milled wheat.