Back in '06 the "Godfather" of the drum smoker posted his "invention" on FB claiming 8hrs of hands off BBQ just like grandad used to make with juices dripping on hot coals and the whole shebang.
He couldn't make them fast enough, the only foolish thing he did was to explain how it worked with all the measurements and equipment needed.
So naturally I stole all I needed to build a drum smoker and got after it. About the same time some dude named Big Mista started one of his own, oddly enough we both decided to put lower doors and removable ash pans. I believe we were the first two from this site to build what is now dubbed the "UDS".
I went on to walk at each contest I entered with it, and Neil went on to becoming rich at farmers markets and then a brick and morter restaurant. Finally becoming a TV star with Arbys, "I don't even cook my brisket that long"!!
I judged a KCBS contest 3 weeks ago and I would say way more than half the teams were using 3 or 4 professional ($400+) barrel cookers.
https://www.bbq-brethren.com/forum/showthread.php?t=19764
Ed