high performance means dust. You cannot avoid this if you want the performance. Like do you expect 30mpg AND 580 hp? Of course not.
And those chucks (itty bitty corner actually) out of the pad is nothing to be alarmed about either. That stuff happens on my race car pads too. As a matter of fact sometimes worst. It is perfectly normal.
1100 : 2-6-12 Order placed at dealership, QDQS6G
2000 : 4-21-12 Oder accepted by GM
2500 : 4-24-12 Order preferenced. Order pulled into production
3000 : 4-25-12 Order accepted by production control
3300 : 5-10-12 Order scheduled for production
3400 : 05-15-12 - Order Broadcast (internal plant paperwork order produced)
3800 : 5-23-12 - Order produced VIN 1477
4000 : 5-23-12 - Vehicle available to ship
4150 : 5-23-12 Invoiced (order is invoiced to the dealer)
4200 : 5-26-12 Bayed waiting transport
5000 : 6-6-12 Delivered to dealer