The graph below shows that ceramic retains heat for the longest between its peers. I am not sure that holding heat is as important as the “heating up” curve. I assume these types of materials react quickly, that is if the base metal conducts heat efficiently.
Kyocera pots are said to concentrate and retain flavours. They claim, the large number of protrusions inside the lid play a key role to trapping the steam, including the flavors it contains, condensing the vapor and returning it uniformly to the inside of the pot.
In this way, the flavor becomes more pronounced, without the vapor being released, and is thoroughly circulated in the pot, making the food more delicious.