The Regency i2500 insert is a great centre piece on the main floor, and the use of the digital thermometer is quite handy. Though I don't know if this is due to poor installation or another factor but seasoned hard wood tends to burn up completely in a hour or two. This is after getting the fire going nicely for a few hours with the average stove temperture of over 500 celsius. The damper being almost completely closed and the catalyst engaged. One of the reasons my wife and I purchased the insert last year was due to the unit's wood burning efficiency and heat output. However as is the insert has to be refueled constantly. A fact I keep getting reminded of. In terms of heat input the i2500 has trouble keeping the main floor, open concept of about 1600 sq ft above 18/19 degrees celsius when colder than -8 degrees celsius outside. Though I suspect the unit is just too small for the floor space. The fan itself, as others have mentioned is loud on high and prone to rattle noises. Overall if I knew what I knew now I wouldn' have purchased the i2500.