Marc Mickelson has posted a review of the AudioQuest William E. Low Signature power cables ($4800) at The Audio Beat. His conclusions:
I've met and spoken to AudioQuest president Bill Low exactly once. He's a reserved and philosophical fellow, and his approach to audio design seems to mirror his personality — serious ideas leading to serious products. While it's true that the WEL Signature power cords, as well as the other cables in the line, have a strong basis in the theory, I am convinced that it is the execution of Bill Low's ideals that makes his Signature line so successful.
In many ways, the performance of the WEL Signature power cords mimics that of the matching interconnects and speaker cables. There is great resolving power and dynamic prowess across the line, and with these the sense that everything remains in proportion. While I thought the WEL Signature power cords were an ideal match for Audio Research Reference electronics, the very effective way they address noise, and let the equipment's true character shine through, will ensure stellar results with a broad range of electronics, the higher the fidelity the better.
I suppose it could be said that the WEL Signature power cords have received Bill Low's personal endorsement. They've also earned mine.
You can read the full review here.