ok cool i thought maybe it was just higher grade and that was why it was higher core. so its just that they tweaked it up a bit themselves
Actually now that I think about it, when the factory overclocks cards they sometimes choose there gpus saying some are "better" than the other ones in some way. Even thought there made the same and everything, but hey who knows they could actually be better.
Up to you really IMO cheaper one will more than likely have the same overclock potential.