The fireplace insert I use deserves an eventual honorable death. It's a Fisher from the early '70s, and is a fine appliance. The house is 50 years old this year, and the insert came not long after. It was built long before EPA certification, and was one of the best of the air tight models. I don't know if their market penetrated the East, but here in Oregon it was one of the top brands. Fisher and Frontier pretty much owned the market.
My Fisher has heavy cast double doors with 5x7 flint glass windows. The firebox is 3/8" welded steel 22" by 16" by 2' deep. The bottom and 6" of the sides are lined with fire brick. Across the front is a slot draft parallel to the windows. Side draft draws in air, anything near the front gets plenty of oxygen, and circulates to the top of the stove, which gets plenty hot to cook on. The flame in front of the windows projects a lot of radiant heat. I can have a gallon of water boiling in 30 minutes in the morning, starting from the previous night's bed of coals.
We are supposed to get a 5 day cold snap starting tonight. I am working on cleaning my wood shed out for once. I'm down to wood that was sitting in that woodshed for 20 years. I just built a fire starting with a 3" ash round on a hot bed of coals, with a 4" and 6" ash split on either side, and a 6" ash round on top of the two side pieces. That would heat the whole house for 6 hours, but I'll break it down into a 4" bed of coals, load a couple 10" rounds, and let it heat the house all night. Right now I'm hanging as far from the stove as I can get. I'm still dressed for cold weather. Cold, clear, and sunny is the forecast. Great firewood weather.
I have to admit that I cut firewood because I don't want to give up my wood stove. It does what it was designed to do, and has done it for almost 50 years. State law says all wood stoves have to be EPA certified or removed and destroyed when the house is sold. I fully expect the stove to outlive me, so I may replace it. If I do, I'll salvage the doors, hardware, and fire brick.