try bedding the pads in. Why the owners manual says take it light on them for the break-in, I don't know, but every aftermarket pad manufacturer will tell you they need to be bedded in.
My friend Dave Zeckhausen has a great writeup on his site:
http://www.zeckhausen.com/bedding_in_brakes.htm
bedding them in will more than likely eliminate the squealing.