I have a central cl-40, 400 gallon storage heating a 1450sq ft house, small 2 car attached garage, a 24x30 detached, and my domestic hot water and I throw a heaping wheel barrel load in every day when I get home from work regardless of how cold it is. Less if its 30 or higher. I have a close friend with a 175 gallon shaver heating 1600 sq ft house and the first thing he has to do in the morning is hurry out and fill it up cause its almost out and he can't go anywhere after work cause by the time he hurries home, the fire is almost out again. Can't even go 10 hours. I left on a friday for a ski trip last winter and stacked a face cord in my firebox and came home Sunday to find out that I didn't need to put any wood in till Tuesday night. Bigger is DEFINITELY better! He gets a hotter burn and is always having chimney fires because of the combustion blower, so I guess one positive is he never has to run a brush down his chimney. I do mine twice a year to keep it from getting real bad. As mentioned above, the little guys have to work much faster creating a clean burn, but I like not having to stand there and make sure the fire doesn't go out. I'm learning that with wood heat, literally everything is relative and a don't think you are going to find one that burns half the wood as the rest, but the trade off is frequency of shoving wood in.