Best cable I know of, regardless of cost, are the Silversmith Fidelium. And Fidelium bi wire. ($1200 8’ $275 bi wire “jumper”) Check out the reviews. They are not the usual “highly recommended”. They all come out and say exactly what I say.
Jeff at Silversmith tells me that he auditioned them in a million dollar system and they significantly better the existing cables. One reviewer bettered what he was using in his $600K system.
And the jumper is unique in that it connects both sets of terminals and has a binding post in the middle connecting to both sets.
They have a 30 day return policy.