I can add my personal experience only -

I have used bpth optical and coax with a $1600 receiver (Not Outlaw) and a $3,600 pre/pro and a $2,500 5 channel amp (Again, not Outlaw).

In each system, the optical cable sounded brighter, nore detailed, more analytial, etc., while at the same time sounding somewhat unpleasantly "edgy" - Listener fatigue after a while.

The coax cable was more laid back and mellow, but depending n the cable, could sound rolled off in the highs. Slightly muffled sound.

With each setup, I gravitated to the coax. I currently use a solid silver digital coax by a small company - No names in deference to the Outlaws. It's more expensive than some, but I have found that it has the detail of optical and the smoothness of coax. If you want more info, pls contact me offline, otherwise no bashing of the Outlaw cables, which I have NOT tried.

Thanks.