Nordost states in it's packaging that the "Power Cord is the most critical cable in your loom". I was running Ansuz cords which was my first upgrade over stock cables. Big difference. Upgraded to Shunyata sigma v2's. A huge difference. I gifted my Ansuz cables to my brother, who replaced his stock cables on his Mac gear with them. He called me so excited, saying he couldn't believe the sonic difference the upgrade made.
@squared80 Newsflash-It DOES matter. I have a very revealing system. If yours isn't, perhaps you can't hear the difference or perhaps you never tried. If so you are depriving yourself. The Cable Co has a library of loaner cables, give it a try. You have absolutely nothing to lose. Then please report back with your findings.