Interesting, this question of mains cables.
Being an electrical engineer (satellite systems) I sit uneasily in both camps namely (a) I know that all cables have different characteristics: voltage drops, impedances etc but (b) does it make any real difference at all or "can you hear the difference in the audio band (20-20KHz)?". I can only cite my experiences, as follows:
1. as you'll see from my profile our audio system has three power amps (treble, mid & bass). My old Linn Aktiv crossover has a fault in that during warm-up it goes unstable for a time and starts buzzing (good square wave on a 'scope on all outputs), but quietens down when good and warm. I've not bothered to have it fixed as I now keep it switched on all the time and it's quiet when warmed up. During the investigation into the buzz, I had everything turn off or disconnected upstream of the XO (i.e. preamp, CD, turntable etc); I also had a Russ Andrews mains cable - one of the 50 quid jobs. One of the (many) things I tried was swapping standard mains leads for the RA lead. Without doubt the tone of the buzz changed between the standard and the RA, and it was repeatable and very obvious.
The most noticeable effects were on the treble amp, and I also tried different "standard" mains cables (which all sounded pretty much the same). So case proven here.
2. Fired up with interest, I bought a couple of RA £30 cables on a two for one offer (OK, I can hear the cries of "cheapskate"...guilty as charged!). I put them on the Meridian CD/DAC and was somewhat shocked by the result; much more top end, and I mean quantitively more, such that I opened up the Aktiv XO and decreased the gain on the treble outputs (which I had previously set higher than "flat"). I confine myself here to the obvious differences, other aspects bandied around in the hi-fi world may be considered subjective (but no less valid).
3. My colleagues at work have been making their own cables based on the RA/Kimber/others woven cables ideas. Today, by co-incidence, I was given one of these and told to try it (yes, Boss!). I put it on the media box of the Pio504. I found I had to re-adjust the picture controls to get back to where I had been ... curious ... especially as I then found that I could decrease the sharpness and actually get a better picture than with the standard mains cable.
curiouser and curiouser.