Picked up a used ceramic 12 this week, played it in a twin for about twenty minutes and I'm impressed. It's not a JBL, but it's warm, crisp, and accurate.
I, too, have a ceramic California 12". I have a Fender Super 60 combo- the pre-amp that Kadlecik used to use with DSO. However, my Cali has the paper cap. It has a JBL D 130 kind of feel. I believe thats what the Weber site says about its characteristics. I got mine on ebay about 2 years ago for $75, I think. I really like it... I felt like I would've had to drive an E 120 too hard and loud to get that much desired sparkle.
Enjoy!
-Jeff