So I keep trying to share around this and few people want to listen. :D
The heavy gauge and tight connections will reduce voltage drop but also puts you closer to all the noise. They don’t do a thing about that, whatever comes in, and even a great deal of house noise, stays in. The last thing I want really is a perfect conductor. I don't know why people think the power that comes off the transformers is necessarily ideal... but nope, can't stop them.
But also please keep in mind those EMI meters are as far as I can tell no more than snake oil. No idea if the frequencies they measure have anything to do with hearing.
In any event what I can say is that I won’t plug anything I care about into a wall without Furman and LiFT and SMP. The SMP filters starting around 3kHz, which is a lot better than most EMI/RFI filters.