Said it once and I'll say it again, unless you are balancing headphones, expensive cable is completely pointless after a certain point, all you can do after the $80 mark in analog cables (estimate) is change the sound signature very slightly by changing cables, you can't get an overall improvement.
Especially in digital cables, there is little to no difference unless you get a complete trash cable. Just get the Dayton Optical from HeadRoom or something in that price range.
Balanced headphones on the other hand, are a huge improvement over single-ended.