I had the same squeal when I changed to the red box pads. Drive them for about 500 miles more or less and the squeal will go away. Antisqueal compound won't help that much. The squeal is annoying, and is caused by the worn rotor surface vs. new pad. Think of it as an old style needle on a vinyl record. Be patient. You can actually see the new pads bed in by looking for the blue haze left on the rotors. The rears will take longer than the fronts. I find the pads work as good as the stock pads overall, with a lot less dust build up.

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'06 X5 4.8is, TiAg/black, cold weather pkg., comfort seats
'07 750Li, TiAg/black, sport pkg.
'05 Ford F350 silver met./slate gray, Lariat, 6.0 PSD, CC, DRW, FX4