Cables are often largely based on marketing and placebos (rather than science) as your belief in the change from
Supra Classic 2.5 to
QED Strand 79 indicates. There would be no audible differences between such products, just your expectation bias kicking in. If anything the Supra Classic is 13 AWG vs the other's 14 AWG so might be suitable for a slightly longer run. Try this website from a former director of McIntosh
http://roger-russell.com/wire/wire.htm. Speaker position or your seating position can significantly affect the sound you perceive, tho (as can expectation bias). Please don't waste your time/money on silly cabling.