I've seen this cable from time to time. I don't think it ever caught on. As I remember it had a pretty good price tag on it. As a rule any 330 cable is worth around $150.00 per pair balanced $100.00 RCA. That's the most I'd pay just to be on the safe side.
I would rate these cables about the same as any MI-330. A couple notches below the shotgun line
