Time is short, so here's a quick summary. Full details and photos are at the link below.
Sammy's BBQ. Adjacent to the Dallas Fed north of Woodall Rodgers. Had brisket, ribs, and sausage. Apart from the sausage (on the right in the attached triptych), which was slightly above the DFW norm, there was nothing worth mentioning (at least not positively). I've had better barbecue at Sammy's on occasion; but not so much better that this performance would bring down the curve.
Back Country BBQ. On Greenville, just north of Park. I've driven by this place countless times without ever going in. Glad I finally tried it. Good sausage from Rudolph's (pictured in the center). Slightly above average ribs, though they seemed like they'd been rewarmed. (I was there at an off hour, though, so that's excusable.) Brisket was tender, with good smokiness and flavor. Crust was lacking and it didn't have the flavor intensity of "eating brisket," but was still above the DFW median. While it's not "great" barbecue, if this is their usual performance level, they're above average for Dallas.
Mac's BBQ. On Main St., east of Deep Ellum. I read about this place on Charles Kemp's excellent East Dallas Restaurants web site and, on that basis, pushed it up the priority list. Mac's used to get their sausage from Rudolph's, but now get it from a supplier in Austin. The sausage (pictured to the left) is different from Rudolph's, but of comparable quality. And Mac's lays a lot of smoke on it, so it doesn't taste like it was just pulled out of the deli case. Ribs were a little greasy and lacking in bark, but had great flavor and very good smokiness. Brisket was too moist (though that's better than being too dry) and the slices I got didn't have any crust to speak of. But it had far more smoke and flavor in it than most DFW brisket. While it's not quite "eating brisket," it's the closest thing I've found to it in my recent DFW explorations. In all, Mac's is one of the better DFW spots I've been to. Despite the texture quibbles, the flavors were all good and they're getting a lot more smoke penetration than the competition. Definitely worth some return business.
After the recent trip to Marble Falls and Spicewood, by first meal back in Dallas was Sammy's. Shock to the system. Mercifully, Mac's and Back Country softened the blow. I'd be interested to hear from any Chowhounds who've been to them. Are they usually that good? Better? Worse?