Thanks for your input. The thermostat/rheostat question is certainly an important consideration. As per the spec sheet of a different unit I found the following statements somewhat answer the question as well as heating times involved:
"... thermostatically hold serving temperature." - that is a good sign I guess, because it will enable me to hold the milk at specific temperatures while ripening as well as after heating the curds (unlike a rheostat)
The unit I found the spec sheet for is actually a Vollrath (http://www.webstaurantstore.com/specsheets/922KETTLECOOKER.pdf
) and the wattage is considerably lower (650W/900W), however, as per their spec sheet they "take a container of cooked food from a chilled state (below 40.0° F [4.4° C]) through the HAACP “danger zone” to 165° F (73.9° C) in less than two hours.". That doesn't sound too bad, especially since I don't need to go as far as 165F and the milk I use is raw milk straight from the goat and still warm ... for aged cheese I simply use it that way, for soft cheeses I pasteurize it, then drop it down only to the point I need it at 85F.
My only concern is that the water bath is only 1/2 liter and I am not sure if that will result in too much of a direct heat. The stainless insert is not really submerged in water as my stock pot is in my kitchen sink. It kind of just sits in a water buffer.
I will certainly will post results if I go this way (my problem is that I am currently in Europe and the unit is more like 125Euro (something in the line of $170 - nearly double the cost of a unit in the US).
In the mean time, if anyone actually has any experiences with a soup warmer, please let me know.