The AC power that comes into your home travels great distances and there are hundreds if not thousands of feet in branch circuits throughout your home. Do you really think it matters if your power cord is 5 feet or 10 feet ? After 40 years in the power and electronic business I can tell you the only thing that actually matters is that the size of the cable be matched with the current consumption of the component and a power conditioner to remove motor induced frequencies.
Power Cord Length
Here's one for the electric wizards to kick around. Whilst attending Axpona this weekend I was doing some power cord shopping. At one particular display I was being told by a very well known cable company representative, I'll not mention the name so it doesn't influence any responses, that the rule of thumb is that in order for the pwr cord to be effective it needs to be at least five feet long. This allows the current to be in the cord long enough for it to be effective. Ok, I'm really dumb when it comes to this sort of thing so maybe I said that in the most simpliest of words but that's pretty much how it was explained. Anyone care to elaborate on this good or bad?