There is really no difference between the
WSM and the ECB, other than, I would assume the quality of the metal used and price.
The concept is the same, heat source under the meat separated usually by a container of water for a buffer.
If you are looking for a set it and forget it, then gas or electric is the simplest, but my personal preference would be wood burner, then charcoal.. in that order.
I've always felt (just my personal opinion) that if you are adding smoke to a heat source rather than cooking with it, the flavor is never quite as pure or deep in the meat.
If you have room, I would suggest an offset firebox.
The advantages of an offset fire box are:
Access to the fire without disturbing the meat (every time you open the container with the meat you start the old thermal rollercoaster)
Better control over exactly how/where the heat goes. (in an ECB or a
WSM the heat can only go up) with an offset box and proper baffles, you can keep your entire cooking container at an even and constant temp.
Of course if you have room, a stick burner provides the most flexibility with what you can burn.
just my 2 cents
