There's not too much info here for those of us using the EKO 25, so here are my results and observations so far: Silicone sealant on every surface possible - I am still having a small problem with smoke pushing past the seal at the flue collar when I first close the bypass damper. Primary air set to 9 mm open each side Secondary air 4 turns out Draft fan shutter 1" open across widest point Burning good dry Sugar maple and red oak I have been able to achieve incredibly powerful gasification with the speed setting of the draft fan at 60%. Any higher than that and the flame turns orange instead of blue and I get burn pockets in the upper chamber which lead to bridging and burn times are also reduced. Of course, with this setting it takes longer to reach a good working temp from a cold boiler, which in my case is above 170*. Using these settings, I get burn times of 9-10 hours with a good bed of coals left, even with the wind blowing to 50 mph and the temp hovering around 10*F like last night. I have a lot of idling due to the lack of storage. Stack temps run right around 300*F when gasifying at maximum. I usually leave bottom door open with bypass open and fan on when starting the fire, and I wait until the stack temp is above 400*F before closing bottom door and bypass. I have been burning continuously for the past week and I have filled one 2 gallon metal pail with ash. Given the amount of wood loaded in the unit during that time - about half a face cord - I think this is fantastic. My next test will be to reduce the primary air openings even more. I am curious to see how long I can push burn times by reducing the primary air. Hopefully this will help those running the 25. The smaller firebox presents some different challenges and settings seem to be slightly different than the 40 or 60.