I thought I'd report that I tried a few short ribs today, for the first time. Based on what I read here, I did a simple rub of salt, pepper, garlic powder, and a mix of some red pepper powders.
For my 3-2-1, I did 3 hours in smoke (chamber at 230). 2 hours in a foil baking pan with a cup of apple cider vinegar, and sealed over in foil. The last hour was in smoke again. To my taste, they were tough. I mean, I had to use a steak knife with them. I'd say they were too lean, because two of the five had more marbling and those were more tender, but not what I'd consider very tender. Hard to get off the bone with a knife, so not even remotely "fall off the bone".
Smoker is a 30" MES, with the digital thermostat and timer. They were more like the ribs hymirth posted than the ones REMSR posted, and marked Chuck Short Ribs. I'll look for one of those bigger racks like REMSR posted.
Mind you there were still rather tasty, and my SWMBO and I enjoyed them, they just didn't come out really soft and melt in your mouth tender like some have said.