As I understand it, the cable must also be clearly labled with its rating to pass code. Several companies make CL rated cables, but sheath them in a 'snakeskin' like material. It may look exotic, but if it covers any of the ratings or doesn't have ratings clearly visible on it, it can fail an inspection.

I've met inspectors that don't check low voltage at all. They figure low voltage can't kill you, so its not a safety risk. But, inspections are completely decided by the governing body having jurisdiction. Everything is open to their interpretation, but in my opinion, its always best to cover your assests.