Use of Si N4 ceramic loose ball bearings
 

To all seasoned Bike mechanics who ride,
The big question is for the loose ceramic balls seen all over the internet. Any good convincing accounts of cleaning out old style loose ball hubs, whether top notch Shimano, Campagnolo or even the more mediocre quality loose ball hubs to replace the steel balls with the Si N4 black ceramic balls with operational success?
The fascination I have is a bit much, but just thought these just might be an upgrade? Forget all the theorizing, did anyone actually follow through and do this and have results after vigorous real use on the roads or trails?