This is a great debate. On one side you have the practical folks who just want to see a blind test for side-by-side comparison. On the other hand you have speaker wire makers who want to feed their kids by selling more speaker wire, and they don't care how it sounds as long as you think it sounds good.
I have seen the best amplifiers money can buy. Two types - Audio Frequency (AF) and Radio Frequency (RF) in the Navy. General Electric built the AN/SQS-26CX SONAR, it transmitted around 3Khz (AF) and used a 80VDC 3000Amp motor generator power supply to drive 576 separate amplifier modules powering 576 (72 columns x 8 rows) in a cylindrical array, for a power output of about 300kW of pulsed power. This system was the largest electronics system in the world at the time ~1976. Whether you counted discrete components, circuit cards, equipment cabinets, or miles of interconnecting cables, it was the biggest. Wires? The wiring was multiple strand copper with Teflon insulation, the best money could buy.
The AN/SPS-49 RADAR was built by Raytheon. It transmitted in the L-band (851-942 MHz) (RF) and could develop 360kW of output power. At this frequency the electrons don't run through the wires, they run on the outside of the wires. Because the inside of the wires are useless, the power feed to the antenna (like a big speaker) is hollow. It's called a waveguide because that's what it does. It is primarily made of copper but the inside is coated with silver. The difference is that the waveguide is pressurized with dry nitrogen to prevent the silver from oxidizing. The tarnish on silver does not conduct at all, that is why silver, unprotected, is bad. The rest of the system used stranded copper covered with Teflon insulation.
Now, if the Navy has to fight a war with its wires, and can afford just about anything, and they use copper with Teflon insulation, that is what I am going to use. The difference in resistive density between silver 166 and copper 150 shows that copper is better by 16 Ohms per meter times the weight in grams/cm2. They are pretty close, but the density is important because it means that a silver wire of 22ga has the same resistance as a copper wire of 20 ga. Or to think of it differently, a silver wire 10" long has the same resistance as a copper wire that is 8" long, notionally. This is why they string power poles with aluminum 72, it has the same resistance as silver when used in a larger diameter (2.30 times larger); even at this larger diameter, the weight is less than the equivalent small diameter silver and much cheaper.
So use silver wire if you want. Just know that my copper wires will have less resistance than yours because I will likely use several sizes larger wire (it's cheap!) and my copper will not tarnish like the silver will. I will also use silver solder (4%) because it wets better, nothing to do with conductivity.
Mark