Residential pellet stoves sound great but in practice they are not reliable (moving mechanical parts that operate at high temps, electronics poorly shielded from said temps—the manufacturers are pretty shady in my experience), and the cost of fuel varies quite a bit and can be very high. Compare to a wood stove that needs no electricity and can burn just about any combustible solid. Modern wood stoves are pretty efficient, too.

If you run it properly. A good wood stove will run cleanly as well. It’s all about the secondary combustion. An open fireplace will not get hot enough for secondary and be dirty.