Hi- I am looking at purchasing a pellet stove insert to heat my 1800 sq foot two story colonial. It has average insulation, with minimal drafty areas. I have narrowed my decision down to the harman accentra, or the quadra-fire mt. vernon. The harmon says it will cover 1450 sq feet in northeast(which is where I am),but the dealer said it would cover 1800 sq. feet. The mt. vernon says it will cover up to 3800 sq. feet. I am looking for a more traditional style, and these two fit the bill, as well as having good ratings. Please advise. I don't want to do an over kill with the unit, but want it to be powerful enough. The harmon is less expensive, but I want to make sure it will do the job? thanks in advance.