I would like to thank Wes999 for the idea. I ordered some 1/4" Kaowool to insulate behind my fire brick in my stove. Its was a little tricky , had to bend out the fire brick retainer tabs a little. Nice performance improvement in my stove. Glad I went ahead and done it. I get a better quicker start up. The secondary flames are more filled out and more of them. A better light show if you know what i mean. Better secondary action at the lowest setting. I would say that getting and keeping temps hotter inside the brick lined fire box equates to a more efficient burn especially at the stoves lowest setting. As I can turn the stove down lower now and maintain secondaries easier.