You know Monster makes 1/4" cable especially for guitarists, jazz musicians, bassists, keyboardists, etc. They state that there are certain features in the cable that bring out the inherent qualities of each instrument. It sounds far fetched to me. It was dumb of me to ask the salesperson if there is really a difference. He told me that he definitely hears a difference and uses Monster cable with his band.
It would make sense that you would want to spend $50-$100 and up on a keyboard cable if you are Billy Joel or something, and if you need a cable that runs 60 feet to carry an unbalanced signal. But for a mope like me who needs 12 feet of wire to play some ditties for mostly memory-impaired folks, I probably was a bit overzealous.
I haven't compared sound with another cable. Maybe I got ripped off $20 - the difference between merely sturdy cable and this gourmet cable.