In the end it s what tastes best to you.
Ceramic or metal burr.
If the burr is ceramic then the transfer is slower and more of the heat generated during the grind stays with the coffee.
For a couple of reasons.
With that isolated variable the ceramic had more sweetness for coffees roasted for espresso and the steel burrs clarity of flavor seemed better for espresso with coffees at production or non espresso roasts.
Ceramic burrs are more brittle than steel so you could chip the ceramic burr if a very hard rock was hiding in the beans.
So steel burrs are more effective at moving heat away from the coffee during the grinding process compared to ceramic ones.
The steel delivers very nice uniformity on coarser grinds any kind of drip while the ceramic generates a lot more fines in the coarser range.
If the burr is made of steel then it absorbs the heat faster moving it away from the coffee.
No flat quality difference between metal and ceramic just different.
Ceramic burrs run a little cooler than steel burrs and there are some coffee experts who think the extra heat burns off some of the oils and impacts the flavor of the coffee.
There s not really any difference when it comes to cleaning.
There are a couple of reasons for this.
However they will retain their original sharpness almost indefinitely.
Both can make fine grinds espresso very well.
Ceramic is harder than steel which means the burrs will stay sharp for longer.
Ceramic burrs require a custom mold or tool to form them.
Small stones and other objects can end up cracking them.
Baratza says that ceramic is good for 1000 1500 cups while steel is good for 500 1000.
Some people also have a preference for ceramic or metal alloy burrs.
The burr set is made from sharp stainless steel and it goes through medium roasted beans like a knife through butter.
Quality of a burr comes much more from its machining tolerances and toothing design ceramic is typically used in very cheap and very expensive grinders.
They start off less sharp than a steel blade.
First off ceramic burrs run a bit cooler compared to steel burrs or in other words they don t heat up as fast or retain heat as much as their metal counterparts.
This grinder is suitable for manual brewing but the company doesn t recommend it for espresso they have a few bigger models such as the e pro and the jx that are more suitable for that.
Ceramic burr are less thermally conductive than steel this means these burrs transfer less heat than steel burrs see below on heat.
Yet it s also more brittle.
In answer to your first question i do prefer the kyocera to the traditional box like grinders with steel burrs.