One reason is that the kind of sintered ceramic used in recent days will not burn like cotton can. It can recover from a Dry Hit when juice wets it again. Cotton can't in many cases. Some manufacturers claim that it is more healthy. I can't speak to that, but the Flavor in the recent ones I've tried is the best I've found to date. The coils are still the same metals used with cotton, so that is not it. The ceramic replaces the cotton at the coil, and in the recent coils I've used (Vaporesso cCell), the coil is embedded in the ceramic and partially exposed at the center air channel in a vertical coil configuration.
It is recommended NOT to glow burn the ceramic to try to clean it in a cCell, but that is because the ceramic is wrapped with two thin sheets of organic cotton, and a dry burn could damage that and degrade the flow rate. The juice flow rate to the ceramic is limited by that cotton wrap. I have not seen an IJoy ICC Ceramic Head yet, so I don't know if they are the same kind of ceramic as a cCell or not.
They make a TC Coil in a ceramic cCell, too. Again, the ceramic delivers better Flavor. You'd have to try it for yourself to know the difference, but I fully understand that a ceramic head is not for everyone. If you are leery of the technology, then wait to use it until there is enough evidence to convince you, or at least make you feel comfortable about it. There are no reasons, other than any you may feel good about. If it's not for you, then feel good about what keeps you off the stinkies. Different strokes for different folks.
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