The performance of the bearings is certainly superior. Depending on their tolerances of course. I use Abec 5 Ceramics in my reels, which are higher tolerance bearings and therefore just fit better, giving the spool shafts and Drive shafts less sideways play and therefore better stability. The reel just seems more "solid" with Abec 5's.
As far as Ceramics go, they do spin slightly faster, but I have not noticed a difference when casting. The best thing about the Ceramics, is that they do last much longer than plain stainless, because the balls don't corrode. The downside with Ceramics is that they are slightly noisier than steels, which can be a little off-putting at first. Some guys are even going with Abec 7's now, which are very high tolerance bearings, but I think maybe that's overkill, besides being very expensive.
