My favorite digital cable under $500 is made by Argent Audio and is called "the Pursang." I preferred the Pursang over Kimber's top-of-the-line digital which costs considerably more. The only other digital cable that I prefer over the Pursang is the current one that I am using, Purist Audio Dominus (this cable cost three times more). Good luck!
Best digital cable below $500
I currently use a harmonic tech platium digital interconnect and am wondering if a better interconnect would make a difference. My system consists of a Theta basic II transport feeding a camelot uther IV going directly into a pass labs alpeh 5 amp to AP Virgo II speakers. Anolog interconnects are Tara labs air 1 and speaker cable is tara labs air2. Thanks in advance for your input.