The more used the better the Rome units work. The finish is pretty rough, I attempted to sand paper my units interior with not much success.
I got this info from a long time rafting bud and it works great for me.
Standard Charcoal Briquettes = 18 bottom and 21 top to bake just about anything. I put down an aluminum foil sheet in the fire pan, arrange the 18 briquettes on that sheet in the outline of the cooker, set the cooker bottom direct on the briquettes. Arrange 21 briquettes on top and you are good to go. You cannot do the rotate routine like you can with round DO's with legs. I spay the cooker's inside liberally with PAM spray and have had good luck. I do not open the lid until the baking smells are easy to spot.
If using a partner steel 4 burner, the cooker's bottom fits perfectly over two burners and is just right for a big group to cook breakfast spuds, sausage, bacon any thing greasy works.
My opinion, the Rome (even the early models) quality of casting is not the best I have seen. I sure wish someone like Lodge (Cast Iron Kings) or GSI (aluminum Kings) would offer the Rome design with legs. Should be a big time item on sales.