After thinking about building one of these for years I finaly did it, but I didn't do it for me.
Gave it to dad for christmas.
Even after reading how stingy they are with fuel I was shocked to see how little it used.
This is after burning full blast with all three vents open (dont know temp, my therm was pegged at 500) for 3 hours, 350 or so with only two open for another 3 hours, then closed all but one and let it go all night (midnight to 8am) it was 235 when I went to bed and 197 when I checked it at 8. Total burn time of 15 hours.
We had 2/3rds of our kingsford left.
And the christmas pig was cooked on it.