Cooked the feta-brined chicken in the PBC last night. Came out quite nicely, although, truth be told, I think I favor the oven cooked version slightly better. Here's how I did it: followed the recipe linked in my original post – brined the chicken overnight. Started the PBC fire by pouring a chimney's worth of well lit coals on top of the rest of the coals in the bottom grate, put the lid on slightly ajar with no rods and let the fire "bloom" for another 20 minutes, at which point the barrel was at slightly over 400 degrees (as near as I could tell). Put a 10" cast iron skillet with 1/4 cup of olive oil in it on the grate, lid back on slightly ajar for about another 10 minutes. While that was going on, I'd rubbed the chicken with the spice mixture from the recipe. Then put the chicken into the now hot cast iron pan, covered it again (with the lid very slightly ajar) and waited for an internal temperature of 165. Removed the chicken (in a now scalding iron pan), placed it on a platter and added feta to the juices in the pan. This time, I added some wine, reduced it a bit and then served the chicken over arugula and topped with the sauce. My wife loved it, but we agreed there was a slight smokiness not present in the oven version and we weren't sure the smokiness was an improvement
Bottom line, it came out quite nicely. And, importantly, we didn't have a splatter-up oven to clean. So, the oven version is way easier (no fire to start and barrel to nurse to temperature), but clean up is a pain (for some reason, our self cleaning oven doesn't self clean all that well). I guess you could say we are intensely ambivalent about which is better: the oven or the PBC version.