It's a cord, right? Well... sorta. Welcome, my friends, to the world of fiber optics. (Some of you have been there for a while - feel free to welcome me, instead, as I think I'll stay for a bit.)
Instead of wire, this cable consists of threads of glass fibers which conduct light (quite nicely) along the length at, well, the speed of light. Light moves much faster than electricity, and when audio signals are digitally encoded and sent as light, the data rate is much higher, allowing for much richer data to be quickly moved about in the same time. The result is much more accurate reproduction of sound. I tried the TOSlink Optical Cable in conjunction with the MixAmp and A30 headphones (also from Astro Gaming), and the surround sound coming out of my PS3 was, simply put, amazing. I had to check to make sure that I hadn't somehow accidentally turned up my 5.1 surround sound home theater speaker system - when I was listening to headphones.
If you have the option to use optical cable, I would highly suggest it - the difference in sound quality is astounding.
As for the TOSlink Optical Cable itself, it seemed sturdily made. The optical fibers conduct light well, even when I wrapped the cord into several tight loops. The outside of the cord has a protective sheath made of what appears to be woven nylon thread. Both ends have metal tips holding the optical fiber with a lensed end, centered in the appropriately shaped connector for optical audio. The grips of the connectors have a hourglass shape and a couple of spots of texture to help you get a firm grip when plugging them in and removing them. Finally, where the grip ends and the cord begins, you'll find some strain-relief designed into the grips.
The TOSlink Optical Cables seem well-designed, performant and provide amazing audio. What's not to like?