There is never going to be consensus in regard to this. Everyone is going to have different experiences. Some homes (for whatever reason) benefit from better power cords, or even powerblock, regenerators, and the like. I saw a review here of a Purist cable where the reviewer concluded that using that cable was a bigger improvement than buying a better amp for the same price.
People are not going to agree, but IN MY EXPERIENCE all better cables make a difference. It doesn't matter what the power company used to get the power to your house. I have replaced all the circuits, cables and outlets, and then the PCs, and all of it was an improvement. Next, I would like to run copper underground from the pole to my breaker box. Maybe I'll buy one of those upgraded breaker boxes for $3000 too.
People are not going to agree, but IN MY EXPERIENCE all better cables make a difference. It doesn't matter what the power company used to get the power to your house. I have replaced all the circuits, cables and outlets, and then the PCs, and all of it was an improvement. Next, I would like to run copper underground from the pole to my breaker box. Maybe I'll buy one of those upgraded breaker boxes for $3000 too.