@mrc4u, a point to keep in mind is that depending on the design of your particular components the length of the cable may be just as important, and perhaps even more important, than the type. See the following paper for an explanation:
https://positive-feedback.com/Issue14/spdif.htm However, while the 1.5 meter length that is talked about in that paper will often be preferable to other lengths (whether longer or shorter), comparisons that have been reported here and elsewhere provide ample evidence that 1.5 meters (about 5 feet) is not always optimal. It depends on various characteristics of the specific components that are being connected, which are almost never specified or known. Those characteristics include the risetimes and falltimes of the signal that is being provided by the component driving the cable (i.e., the amount of time it takes for the signal to transition between its two voltage states); the susceptibility of the connected components to ground loop-related noise that may find its way to various internal circuit points in the component receiving the signal; and perhaps also to the high frequency components that correspond to distortions of the signal waveform, that may result from reflection effects caused by small impedance discontinuities and which may also find their way to various internal circuit points in the component receiving the signal.
While of course it would be preferable to compare a number of cables of various types and lengths, perhaps via The Cable Company, at the very least I would make a point of trying to determine what cables others have used with components that are the same or similar to yours. In that regard it appears that shkong78 has given you excellent advice.
Finally, regarding the disagreements that have been expressed above, IMO it is certainly possible for digital cables to affect sonics in various ways, including ways that can be subjectively perceived as differences in tonality, soundstaging, etc. However I would not ascribe specific tonal or other sonic characteristics to particular cables, as such differences will largely be a function of how the characteristics of the specific cables interact with the specific circuitry in the components that are being connected.
FWIW, IMO, YMMV, etc.
Good luck. Regards,
-- Al