Throw a really attractive lure into the depths and lets see what we can catch. The joys of trolling. Seriously, if this a legitimate topic of interest, consult the archives of this forum and other sites. This subject has been covered, debated, and fought over at enormous lengths.
http://www.head-fi.org/forum/thread/139344/power-cord-shoot-out-14-power-cords-reviewed
This was one attempt at summarizing what one person heard when trying to answer the question you ask.
http://www.head-fi.org/forum/thread/139344/power-cord-shoot-out-14-power-cords-reviewed
This was one attempt at summarizing what one person heard when trying to answer the question you ask.