Erik, you are right about measurements on a bench. I can hear the difference b/w silver, copper and gold though. I don't care what the measurements say. Just my opinion and experience. Everyone is different. I don't believe that super expensive cables are worth it unless you have an amazing high end setup w/ extreme sensitivity.
Usage in a real setup results in distortion generally induced by outside interference. The longer, thinner and plastic wrapped cables pick up all kinds of crap.
I always hook my friends up with something decent when I spy they are using 24 ohm speaker cable on a 100 foot run or a 12' rca for a 1 foot connection lol.
Just yesterday I hooked up my friends new tv. He had the old Pioneer 515K receiver that I traded him and some old decent bose 901s and an old pioneer dvd and digital cable box. Just using the proper cables like a $1 shielded, metal optical and coax digital cables for the cable and dvd, 14 ohm speaker wire instead of the 24 ohm he was using, a real hdmi cable, plugging the receiver directly into the wall changed the sound from what are they saying? to WHOA! for him anyway. The room is a nightmare but at least now you can hear most of the audio. His family is happy as hell and enjoying the best system they have ever had. Cost? $30? maybe. Free to him. I just used my scrap cables.
He has twin 5 yr old boys. It was so worth it to see them light up at Star Wars: Clone Wars cartoon cranked up. They were bouncing lol.