Well.. actually there are some MINOR spec changes sometimes. A JCRG-2 and RG9570 are actually the same guitar except for the
trem block. A JCRG-2 would have the HS-HV Steel trem Block like an OFR.
But aside from the very minor details, it's just Ibanez's marketing dept that wants to make it look like they have new models out by re-releasing the same guitar under a new name. (why is it that we all love this company even though they don't make thier own guitars?)