Wearing in one thing, but cracking ? I would take them off and get a closer look.Usually the only way they crack is if you have them turned and you go below the minimum thickness listed on the rotor.
As far as a quality rotor, I've never tried them, but check this out:
http://www.cryogenicsofindiana.com/prod01.htm
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\"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.\"
Benjamin Franklin, Historical Review of Pennsylvania, 1759
www.cybermopar.com
TripleJack