Since I've never seen a write-up of a properly controlled blind test of biwiring, and the reports here are subjective, I'll add my own subjective opinion. I've never heard any difference (and I've never seen a rigorous scientific explanation of why there should be an improvement.) There may still be an improvement that I can't hear, but I'm sticking to my basic philosophy, which is that...it's all about crossovers. If the crossover is right, wires, terminals, designer caps, interconnects, etc. don't much matter.