Single ended: The Goldpoint is more detailed, has better high extension, better bass extension and is "faster". The RPX-100 is fuller and warmer, but less refined.
Single ended I prefer the Goldpoint in general, but it depends on the combination. The DX1000 I prefer plugged into the Goldpoint, the GS1000 I prefer with the RPX-100.
There is never a simple answer, because there is always personal preference and synergy....
Just speculating, thanks.