I can only speak for Southern Prides, they use wood, logs or splits, for smoke. The unit my friend has uses gas for heat. He does get a smoke ring. It is pretty set and forget, as much as any one I have heard of.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"I'm Armenian...perhaps...but then again...maybe not..."