@oberoniaomnia very interesting to hear your experiences! Wow 90V drops!! I thought mine was bad for being between 124 and 126 
I wonder sometimes if this cable thing is a system thing. Like maybe some systems are more sensitive? I don’t want to say "better" because I have no idea what your system sounds like and that would be a cruddy thing to say. But maybe it’s more just about certain speakers, amplifiers etc having more sensitivity to wiring changes. Or maybe your stock wiring is just amazing?
If you get a chance to try out some shunyata cabling, do it. I had tried several bran ds too and was in the camp of "I don’t know if I hear anything different" whenever I would try different speaker cabling. For example, going from my amazon basics wiring to mogami wiring was like "hmm I think I hear a change" but then going from the mogami to the shunyata it was like "holy crud - it’s not subtle at all!". My amplifier doesn’t have an A/B so to be fair, I had to swap cables or have a friend do it. But in most cases I could discern little differences, except in the case where I purchased the component or cable. It has to be clear in order for me to shell out funds.
The same goes for power conditioning. Not impressed at all with the ones I had tried thus far until I tried out a gemini 4 from shunyata, and ordered a gemini 8 immediately since I have a 20 amp line. Difference from gemini 4 to 8 was not noticeable at all just as a side note.
I am actually about to head to the hi-fi shop to try some high quality interconnects, the final frontier for my system. I am super skeptical again about these having any noticeable or beneficial improvement to my system. But I’ll be happy to be wrong as I was about speaker cabling and digital cabling!
Friendly note to those buying cabling: find yourself a hi-fi shop. They will usually cut massive discounts on stuff you’d pay full price for online. And let you try before you buy! PSA over