I would like to comment on an experience I had, not with cables, but an electrical outlet. Jonathon Spelt at Ultra Fidelis in Wauwatosa WI helped me upgrade my system with Vandersteen VLR Carbon speakers, REL T7 subwoofer, Aurender N200 music server, and full Audioquest cables. He also sold me an NRG Edison outlet, which I did not immediately install because, well, I was lazy and how much difference could it make anyway?
I recently installed the outlet and, oh, my, what a difference it made! The individual sounds became more focussed in space and there was more empty space around them. I could go on with the usual superlatives, but I just wanted to say, don't stop with the cables!