PC Amazo never faced anyone of cosmic significance, his power is also susceptible to being absorbed quite easily (GL did it several times), and PC Aquaman (who was much weaker back then as he barely had any super strength at all) was able to KO him.
Protege, on the other hand, was able to mimic the powers of the entire cosmic hierarchy and his only limit was that he was unable to mimic an unseen thought, though he later adapted to that and was able to mimic the omnipotents (LT & co).
So what im trying to say here is, Protege utterly stomps.