Nordost Blue Heaven or Tara Labs Prism Helix 8

I have to buy new and longer speaker cables to my B&W 705 speakers. I recently had 2x4 m Nordost Solar Wind, but I am wondering if I should upgrade to Blue Heaven. Unfortunately I have to go for 2x6 meters because of my speaker positioning. I have a Primare A 30.1 integrated amplifier, and use a Red Dawn interconnect with my Denon 2900 cd/dvd-player. My local dealer tells me that Tara Labs has a cable, Prism Helix 8, that is specially made to go with the B&W 700-series. Any suggestions?