I do make my own rub but I use the ever so fancy Sweet Baby Ray's Hickory and Brown Sugar Sauce. Took the dome to 275* then put baby backs on meaty side rearward. I didn't think about them, well, I didn't check on them for another 3.5 hours. Temp was about 260*. I sauced just the top and nudged the vents a bit. Another hour and they came off. Dome temp was 290*. I let them rest uncovered in the oven on a cutting board for about an hour.
Very simple cook, but man, this is good.