Considering they have the same moves and typing, Im pretty sure a 1490 Rhydon would perform better than the Rhyperior so maybe just level up instead of evolve. The reason would be that I think percentage wise Rhydon gets less of its CP from Atk than Rhyperior does. Honestly there may not be much of a difference at all and a pretty small one if there is.
I doubt that either is a particularly great performer though.