said by alkizmo:As for combustability of teflon, I don't think it's much important to buy teflon if it's much more expensive or hard to find.
Plenum cable (CMP rated) is readily available everywhere cable is being sold and while indeed more expensive, it is not so much more expensive that cost becomes the reason for a homeowner not to buy it.
I remember seeing a video showing the difference in flame-spread and smoke development between CM (General Purpose), CMR (Riser) and CMP (Plenum) which was sufficient for me to spend a few extra dollars even if the code doesn't require it (I thought it was at the UL website but couldn't find it now).
With all the combustible material in a typical home a fire will spread regardless what type of cables you use. However plenum cable will at least not actively help in spreading the fire around (as plain PVC will do).