Looking for some advice...currently run a Quad grand voyager in a 3,000 sq/ft house. The stove supposedly produces a max of 52,000 btu with a firebox of approx 2.5 cu/ft. My question is I see stoves with almost identical sized fire boxes producing almost 50% more heat. Most around 75,000btu. Why is that? Are some stoves just better at throwing heat than others? The hearthstone Clydesdale really catches my eye. Also the Osburn 2400 is a tank at 100,000btu but with a larger firebox at around 3.3 I think. Is it basically all in the size of the firebox and the btu numbers these manufacturers say are just BS?