John421,
Simple answer is different systems, rooms, ears. They are great in my system, hands down among the best I have ever heard. I do believe they like SET, tubes in general. I cannot praise them enough. In my rigs they replaced extremely expensive silver. At any rate different ears that I respect with different rooms and systems love them better than almost anything else they ever heard or owned and we are talking high priced cables; and even then it is usually a split decision. Best, Rob
P.S. How can you go wrong comparing them against anything you own? Only about $50.00, 1 meter terminated RCA.