Teflon also has a very low dialectic constant so you can make all kinds of multi-wire braids and still end up with less capacitance than plain PVC insulated cable with just 2 to 4 wires.
It's non stick properties are also quite useful for headphone cables since it keeps them from catching of snagging on things. On the other hand, the teflon makes the cable kinda stiff. It is distinctly un-supple and will never lay nicely in a coil; always unwinding itself instead.
XLPE is very close to teflon's dialectic constant and quite a bit softer, but it seems to be quite a pain to get your hands on any plain XLPE insulated wire. The last time I looked it was basically strip it our of some Canare star quad yourself (cheaper than the equivalent Mogami), or find someone on ebay who already did it for you.
