Cable recommendations for cary slp-98p & cary 120s

Looking for some reconditions over copper or silver interconnects for my cary slp98p to my Cary 120s power amp. I am using Kimber silver streaks from my cary cd player to my preamp and made a huge difference in clarity and image and speed. But should a person go with copper for preamp to power amp or silver be better signal transfer?

Also would a Shunyata Zi-tron cobra power cord be a good choice for a cary power amp? Since i have shunyata viper Zi-tron power cords for the rest of my system."

Let me know your experiences