BBQ1 was featured in Atlanta Magazine's recent BBQ issue and I've also talked to people who know their food. It's on Lower Roswell Road in Marietta. Although there is the usual new construction in this area, BBQ1 is in an older, nondescript strip mall entirely appropriate to a BBQ place.
I ended up at the takeout window because the dining room isn't open for Sunday dinner. I drove my rib plate home; the aroma gave an air of anticipation to the drive. I really enjoyed the ribs. I find them to be more traditional and authentic than some of the rib places inside the perimeter (it seems that I can learn to overcome my ITP snobbery). They were just a little toothy to give a nice texture but still moist. They weren't slathered in sauce as a finishing coat, allowing me to add the amount of sauce that I wanted. The sauce itself was very subtle---flavorful but not trying to be over-the-top on heat or anything else. The beans and cole slaw were both excellent.