A few years ago I was going to install some ceramic bearings in the race bike. There was a lot of information favoring their use from folks that were making money from selling them exclusively or as a prominent product line. So, in the quest for an less biased or more honest opinion, I asked for advice some tech advisers at reputable bearing companies that sold mainly ferrous and a limited amount of non-ferrous bearings.
These are some of the things I was told. First, manufacturing precision in conventional ferrous bearings is a big deal and it helps to lower friction in typical uses more than the use of exotic materials. Second, bearings in an oil or grease bath will have a lubricant film between the bearing elements, so exotic materials do not offer big friction reduction benefits. Third, ferrous wear and failure debris can be removed by magnets such as on drain plugs. This is an advantage. Last, exotic materials may offer benefits if there is an electrical current passing through the bearing that is pitting the ferrous elements, the bearings are in a corrosive environment like brine, or they operate at very high rpm, in heat, or with no lubrication. There was other things they said that I do not remember.
A motorcycle wheel hub might be one of the better places to use them. The only lube would be a light film of grease on the ferrous parts to keep them from rusting. Lubrication friction would be minimized. This change would cost $$ so I needed some unbiased third party engineering information about friction drag in that application for both lubed ferrous and unlubed ceramic bearings. I could not find any, so I stayed with ferrous bearings.