1- I suggest to try those AC female connectors last as they are hardest to remove in case you want to back step or change mind. I was skeptical when I first try these 3 enhancements so, for that, I first applied on connectors with open flat surface first like speaker spades, AC males, RCA, XLR males… they are easier to wipe off than the females…once you are sure and satisfied with the new sound improvement, you can go on and apply to those females connectors and the rest of the system.
2- Can’t confirm how easy that’d be since I have not tried on USB or Ethernet cables. Keep in mind Q45-T isn’t as thin as 1260 but actually thicker with some grits like sand in it, as mentioned. (Also, the brush from 5mL bottle Q45-T is bigger than the brush from 1,5mL bottle nps-1260)
John