Well, ceramic bearings are more wear-resistant than steel bearings, but not as tough in fracture. If you've got loose BB or mis-aligned shell, the bearings would wear faster resulting in ovalized bearings. However, if they're chipped and cracked, that's a fracture issue from impacts.
Been practicing for the Paris-Roubaix race???
As for the creaking, too frequent uses of the facing/chasing tool will result in creaks. Each time you use it, it shaves the threads a little and increases the tolerances between the BB and shell threads. Wrap a couple layers of teflon tape around the BB cups before you install next time. I've had to use as many as 5-layers to tape on some configurations to stop the creaking.
Last edited by DannoXYZ; 06-18-09 at 01:26 AM.