Been burning pretty much all softwoods since I installed my insert. Hardwood is pretty tough to come by here unless you can scrounge it from town or buy it. So it's been about 90% pine, 10% W-fir, and 10% D-fir. I have been chasing the elusive 12 hour burn since I put it in. Especially with the pine I can't pack the stove or it wants to take off and overfire so I have been getting 3-4 hour burns, 5 tops and waking up to a 200 degree stove every morning. Friend of mine just gave me about 1/2 truck load of good dry scrub oak he brought back from Utah. I put 2 4" rounds and 2 splits in last night (nowhere near packed the stove). 1st I am amazed at the smoldering capacity of this wood. Usually if I damper down pine to quick I get smoke. This stuff almost looked like it was going to go out but kept a few lazy flames now and again and never any smoke from the chimney. The stove rose to about 550 and stayed there. So here I am 8 hours later and there are still 2 well defined rounds in there (all coaled though) and the stove is at 400 and holding. Think I will treat the rest of the oak I have like gold and ration it out for only the night burns from now on. Should have enough to get me through January. I have always been adverse to buying wood but I'm thinking I need to find a source to get at least a cord of good hardwood even if I have to pay for it. Loving this stuff!