No way thats with an insert, right? I dont think Ive ever seen anyone post those burn times with the insert.
Those times are from ashfords burning extremely high btu wood. Remember how these stoves work, the thermostat tries to maintain a specific stove temp which on lower burns is really just a cat temp. The firebox is mostly just a fuel tank. Ashful's fuel tank is a little bigger but filled with fuel that has much more energy per gallon.
My princess is bigger than his ashfords but I can't match those burn times with my low btu Douglas fir.