Friday I went to the building, to the apartment that's our's, and tested the new water heater's capabilities....
So what I did was first started the dishwasher, then took a 20 minute hot shower. By then water heater temp was down to about 110 by the time I turned off the shower (thermostat set to 140), dishwasher filled and emptied a few times during that time as part of it's normal cycle.
Then to top it off I decided to run the top load washer at max water level on hot with warm rinse, about 5 minutes after the shower. hot water temperature hovered at about 110 during the whole time it filled and once it stopped filling the heater caught up again...fast.
So overall the new water heater does about what I expected, it supplies plenty of hot water for intense hot water use between tenants and after some long use hot water runs down but not out.... Just what I wanted, and once hot water use susbides a little the tank catches up more than enough for another shower or the rinse cycle of the washer, fast.
So overall I'm very happy with the hot water supply now. Next up in who knows when time will be the rusted through 1" water main in the basement...