the 320 wagon we bought 2 months ago had Pagid pads with ATE discs, with routine wear, only 1/3 worn. they screeched like crazy, not squealed, screeched; yikes, what a nightmare, ear-piercing!
I switched to PBR pads and ATE Powerdisc grooved rotors bought via FastLane. Ooh, the peace and quiet. how nice. and yes I applied the paste before, but it didn't help.
My guess is that the verticle groove down the center of the Pagid Pad created a harmonic under just the right pressure, which was at about 2 mph, crawling in traffic, just before full pressure for a complete stop. But that's just a guess. What a racket.
PBR are also very low dust, we have them on our BMW, they stop really well, are quiet and are indeed amazingly dust free.
1995 MB E320 Wagon
2001 BMW 530i
2007 MINI Cooper S (!)