I have a block logo A Zildjian,18" thin crash that I picked up on the cheap with almost exactly the same cracks.I drilled small holes at the end of the cracks to stop them from getting bigger and in stalled a small bronze grommet.It has held up for quite some time now,but I wouldn't recomend it for metalcore.Come to think of it,I don't know what I would recommend for metalcore.Anyway It does work well for classic rock though.
Steve B