I received my Zcable "Thunder" power cords this afternoon and have spent the evening listening to them on my amps. They offer exceptional performance. I am especially struck by how how coherent they sound compared to the other cords I have tried. I also noticed this coherent quality when selecting the "Thunder" cord for my preamp. I finally have the performance I have believed my system was capable of achieving.
BTW, some of other products I have recently adopted are, Walker High Definition Links Mk. II, Marigo Audio VTS tuning dots, Zcable "Live" balanced interconnects and Zero autoformers(primarily of interest to tube amp users).
All the products mentioned have excellent price/performance ratios IMHO and have provided dramatic improvements to my system.
Life is good. God bless.