My house is a 23 yo 2200 sq ft two story center hall colonial. I was planning on buying a pellet insert which would be placed in the back room open to two other rooms. Quadrafire Classic Bay 1200i since it states it heats upto 2500 sq ft. The Mt Vernon heats 2400-3800 sq ft. I had read on line that buying a stove too large for the house would lead to the unit having to run on low and not be as efficient or heat the downstairs too much. Do you agree? Appreciate any opinions out there.