I’ve purchased a handful of Signal Cables used...all the Magic Power Cable in various sizes. They come up occasionally preowned at good prices. But even new they are a great deal.
I can’t compare them to higher end cables but I can compare them to the standard IEC power cords that come with most components and in my stereo, I perceived instant improvement from inserting these...especially on my amp and preamp.
In terms of the DIY suggestions...are there any resources out there that illustrate various methods? This is something I’d like to try. Soldering or screwing terminations to raw cable seems simple enough but I know there are some more esoteric methods as well that may help with noise or filtering.