The "squeal" is not from the ceramic pads but from them vibrating on the caliper. This is common on semi metalic and ceramic pads that are using a harder compound than the cheaper semi metalic and organic. To remedy this use some brake quiet grease or compound on the back of the pads. Cermaic pads do not have any metal in the compound, they use a ceramic material that is extremely hard and does not wear very fast. It leaves a grey/white almost clear dust that does not stick very well to stuff like the semi metallic dust does (semi metalic dust is mainly iron dust which is why it makes your rims a red rusty color.) You may also notice with Semi metallic pads that you will get little to no dust on the rims untill a rainy day or a very humid day then all of a sudden BAM dust everywhere and your rims look like hell. Well that is because the dust went from happy raw iron to rust in a few short minutes and that stains the rims quickly.

Massey