I agree, for quick grilling lumpwood can't be beaten. But for a long cook, I find briquettes are ideal, & easier to regulate the temperature.
Mrs Aks bought me one of these to replace the beer-can. The dome is filled with liquid of your choice, put the spikey thing on then put your chook over it. Next put the cap on. Very little steam comes out the top of the chook.
The cone holds the poultry upright, which allows the pan to catch all the juices that can be used for basting or making a delicious gravy.