Here are some of my thoughts after 72 hours of break in on my CPT300.First I want to mention that had problems inserting the female connector into my Spectral preamplifier, this is the tightest fitting cord I have ever used in my life. Out of the box the CPT300 sounded OK with blacker backgrounds than I was accustomed to and there was some extra detail. I waited 24 hours and went back for a second listen and the system had more separation than my previous very expensive power cord. There is a lack of color with this cord while giving my system extra micro detail that I have not heard before. After 72 hours the CPT 300 continues to increase in frequency response, deeper bass and a touch more top end. I would say that things will get very interesting over the next 500 hours because currently after 72 hours this one of the best power cords I have heard. I will be ordering another one next week. I have own several of the mentioned expensive power cables on this thread from $5000 and down and I would prefer not to put any of these other cable manufactures down, so no name calling here