Ironically, I have been looking at these numbers quite closely as our tasting room where we planned to sell 4, 8, and 16oz samples of the beer has come under quite a bit of attack by local residents.Dark Horse here in MI made 9300 barrels last year with a 7 bbl system. Not a nano, but you can be making a lot of beer with a system of modest size.
In our market, with my overhead (rent, utilities, etc.), using the standard sixtel pricing in our area, I would need to wholesale 500 barrels per year to break even. That is a lot of brewing on any system less than 10 barrels. That is self-distributed of course, if I had to use a distributor, it would be more.