Depending on how fast you want it done, I usually run 225 if I am not in a hurry to 325 if limited on time. Keep a drip pan 1/2 full of water under the chicken (on top of the deflector) to catch the drippings.
I have calibrated the temp probe on my 380x with a Thermoworks Square Dot. With no peeking, it holds temps well. I calibrated it to 350 as that is where most of my cooks are intended.
With our RT-700 and now the RT-B380X, our oven in the kitchen is now a glorified pots/pan storage area.