Ceramics provide good even heat distribution. However, they have some disadvantages. They are slightly more difficult to keep clean compared to stainless, and ceramics are less durable than stainless. In most gas grills, the ceramics sit in a tray and they are evenly spaced to help with heat distribution. While cooking, the ceramics absorb grease and drippings and create smoke to add flavor.
Metal - Less even heat when compared with ceramics, but metal is easier to clean and more durable. Typically, these flame tamers are made of stainless or porcelain coated steel but stainless is superior. Metal flame tamers have two variations, burner width and full width.
This is an angled piece of metal directly over each burner. This shields the burners and reduces flare-ups but creates less flavor than full width. This type of flame taming system is often referred to as “flavorizer bars”.
A solid or perforated metal across the entire grilling surface. Full width delivers more flavor than burner width and the burners have more protection. This type of flame tamer typically has more even heat distribution than burner width.