I use Cowboy charcoal - it works great. Sometimes I will layer it on the bottom of my PBC charcoal basket, - about 1/2 of the total volume of charcoal I intend to use - then top off with Kingsford, or other briquettes. I get the briquettes lit and burning to the desired stage of ignition - which for me is a good amount of red showing with some white ash developing - when looking down on the large Weber charcoal chimney ) - then dump that on top of the unlit Cowboy lump - already place in the PBC basket.
I allow about 15 minutes with the barrel lid partially off - for the heat to build and temp to settle in -then load with chicken.
Lumps burns hotter - and not quite as long as briquettes, so it seems to give me desired temp. range for a longer period of time. Once the briquettes are burned down enough to begin producing as much heat - the lump begins to contribute more - and - it works great. I have done 2 full loads of chicken ( 8 whole chickens, split lengthwise into halves, and hung on the hooks in the PBC ) on 1 full basket of charcoal this way.