Having experimented with numerous cables for years,Tara, Kimber, Stealth, Nordost, Shunyata, Audioquest and others as mix and match and otherwise, I am a firm believer in the loom theory. Every cable has a character. Some provide better leading edge, some better tone, some lusher mids, some fuller bass, others more impactful bass, etc. As there is no perfectly neutral component, there is no perfect cable. Among the above brands, there are no slackers and none with any major weaknesses that I've heard. But for my system, there was one that I preferred as a complement to the sound of my components. Whenever I inject another brand in the mix it interferes with the overall sound that I'm after. Now-- if a source component needs a boost in one area or a little bit of tempering on another (e.g.-high end too brittle or too prominent), I have, in the past, put the appropriate cable in that spot. But for me the better solution is to gather the components that best provide the sound you seek and then wire the system with a loom that does no harm to or complements that sound. This goes for cables. I have not experimented with power cords in the same way so I cannot say that they form an essential part of the loom.
Others may decide to color each component. I guess I just don't have the patience for that.