The best "sounding" PC I've tried on my GS-1 is generic 14/3 unshielded cable that came packaged with my Parts Express 500W subwoofer amp. I've tried others but they all had something about them that didn't sound quite right...
D.I.Y. VH Audio Flavor 2: midrange too forward with glare
Signal Cable MagicPower: rolled off in treble
Volex 17604: bass and treble rolled off; midrange kind of "bloated"
Unfortunately, stupid me overshortened the Parts Express cable when I tried to reterminate them with a Marinco plug.

I don't see it listed anywhere in their catalog so I can't order a new one. Right now I'm using Carol 14/3 unshielded wire with Marinco IEC and wall plugs and it sounds pretty good. I'm going to try the Iron Lung Jellyfish PC in the near future.