I haven't read much into optical cables, but I did study fiber optic cables a bit in school.. They use a phenomenon called TIR (total internal reflection).. This is when a light beam is reflected off of internal walls of the cable which allows light to be bent around corners, this phenom. is also responsible for the sparkle which is seen in diamonds and other gems.. TIR is strongly dependent on material. If the material is not pure or if the outer walls of the material is not VERY smooth, degradation of the signal is definately going to occur, jitter is also commonplace in optical cables.. I'd recommend spending as much as your budget allows on your optical cable.