"Power Cords-More Recent"

Have a two old PS Audio power cords in my stereo system that I purchased used in 1999 when I lived in Dublin Ohio (don't remember the model) for about $400 each. One is connected from my CD player directly to a Panamax 6 Protection Path,  and the other is connected from my integrated Amp directly to a Panamax AC 5510 AC Regenerator. My ACRegenerator is connected to the Panamax 6 with an MIT Z Cord II power cord which is plugged into the wall. My question is does anyone know whether current power cords are significantly improved in sound quality to justify replacing my current power cords with new ones? I don't intend to break the bank so $400 each is as much as I want to spend. I am using Kimber speaker cables, digital and interconnects throughout my system so in addition to Kimber I plan to  look at power cords from Audio quest, Morrow and Wireworld. Also, Should I just connect both power cables into the ACRegenerator and stop using the Panamax 6? Your thoughts please.