Krellman: Stevemj is correct: power cords are not in the signal path and therefore will not improve the performance of your equipment.
If you want to really evaluate power cords, set up an ABX test between two identical pieces of equipment: one with its stock cord, and one with the VanDenHul power cord, or any other kind. Match the levels to within 1/10 dB, and use the same program source for both. See if you can detect an audible difference between them.
