Nights have been dipping into the low 40's/high 30's as of late so it has been a perfect opportunity to test out the new insert, and also get the paint baked on. I have to say that I am disappointed in its ability to warm the house. As feared, I am really regretting not getting the larger 3100. At 2,200 sq ft i realize I am pushing the rating of my insert, but was hoping for better results. Last night we got down around 39 deg and the highest I could get the living room was 75 deg with a full load of seasoned oak, full open damper, and fan on high. Now I agree 75 is plenty warm for a living room, but we are only in Sept, and 39 is not cold for a winter night in WI. My brother and sister in law have a Quad 5100 in their 1800 sq ft house and last Dec they had to open the windows when it was 10 deg outside because they got it too warm. I can see now that mine will not be able to do that. So the question is are my expectations too high for this unit? My house has a pretty open concept with a large open living room and dining room, with a family room off to the side. It is going to get much colder in the near future and I can see I am not going to be happy with it. But I don't know what to do because it is now a used unit. If I try to sell my 2400 and buy the i3100, I will loose a lot. Or I just live with it and learn to accept it.