We lived in the DFW area for 15 years before moving to SW Ohio ... granted not subzero weather, but a good constant 20’s at night. We had a a conventional mortar fireplace... and put an “airtight” insert in it. It did have a blower but we seldom used it. To hot with it in that room.
During the late after noon, early eve ... I wold open the intakes to burn hotter ... that minmizes creostoe build up, but at night I would shut the air off almost completely and 4 good sized logs would last all night.
2200 square feet on one floor .. we used a small box fan in the hallway to aid circular air flow through the house and very seldom did the furnace ever need to assist.
Big downside ... as in insert in an existing fireplace, there is no room for an ashbox under the firebox. Every two or three days I would let the clinker bed die down to almost nothing, shovel the ash into a metal ash can (metal is important ... hot hot clinkers) and haul them out. Messy job
A free standing unit is by far more efficient and easier to maintain. Most have an ash bin/drawer
I have a Soapstone airtight stove in my 32 x 28 wood shop in SW Ohio, and I stay nice and cozy with wood heat alone. It is 10x more efficient than the fireplace insert, and easier as well. Downside in a woodshop ... finishing unless water based is volatile. that and dust particulate. lol Was a good way to make the case for a complete dust system.
I guess it all depends on the size of the fireplace. Our insert has an ashbox. Our insert also sticks out 14 inches from the wall and we can cook on the top of it.