I have experience with both the Napolean 1101 and Jotul 550. Both are steel inserts with cast iron faces.
The firebox on the 1101 starts out tiny and is subject to a buildup of coals when you run it for a long time. It heats up quickly and consumes its fuel quickly. I feel like I'm feeding it all the time but it doesn't eat much at each meal. The blower seems fairly weak to me, but it is nearly silent and does blow the air downward which warms up the floor quickly. Its easy to damage the refractory in the top of the insert if you like to jamb the thing full like I do.
Those panels aren't very expensive or difficult to replace. This insert is inexpensive and probably the right size to supplement an 1350sqft house. You will probably need to use other heat when the temps drop below zero.
The 550 is built better and looks better. It should for twice the price. The 550 takes a while to come up to temperature, but once it does it throws a LOT of heat for a LONG time. The blower circulates much more air, but the blower makes more noise on high and is aimed upward. You will still get more airflow on medium where it is pretty quiet than you do on the 1101 on high. You do need to heat the whole room before the floor warms up. It's probably the right size to heat a 1350sqft house on those -15 degree nights you get every 10 years. It will take a lot of practice not to hit 80 degrees inside when its 30 degrees out.