The cookshack units are airtight-no vent. I asked about cold smoking and as to how to maintain smoke w/o exceeding 100*f. They have what they call a cold smoke baffle which is kinda like a water pan which they recommend that you fill w/ icewater. They described a process which involved exactly how much wood to use, what temp to set at, and how long to smoke. It was obvious that they had made a science out of it. They really seem to know what they're doing.
I guess that's what turns me off about them, it seems like it's all science, and no art. Like I say, Famous Daves uses their units. If you eat @ FD's, you'll get the exact same thing every time @ every store. It's the exact same thing, but I don't think it's anywhere near as good as what I cook.
I suppose real pit masters are hard to come by, and probably expensive to keep. If you had a chain, you probably wouldn't be able to find enough to staff all the stores. Maybe that's why places like Arthur Bryant's, and Gates only have one store, and are famous.
BTW, Cookshack has some really nice color brochures, and some really nice people that could, I'm sure, answer any questions you might have.
Good Luck, and Good Smokin',
Tim
Oh, and Coz, When are you takin' me fishing?