The Positive Reedback review was of the power cords. There is a review of the GS speaker cables in Audiophilia -
where it was awarded an 'Audiophilia Star Component' award, fwiw.
It wouldn't be appropriate for me, as the manufacturer, to make comparisons, and I can only suggest you avail yourself for the 30 day money back audition policy through tweekgeek.com
The GS speaker cables came out after the GS power cords, and the non mains specific enhancements that are incorporated in the GS Mk II power cords, are already incorporated into the GS speaker cables.
Hopefully, you'll be able to compare speaker cables in your own system, which for you is the only comparison that really matters. I'd welcome the comparison of my GS speaker cables to any of the K-S cables, or those from any vendor.
Many thanks for your interest,