I too have most of power tweeks as yourself. For Nordost, 2x QX4 and also have several Addpowr symphony's.
Also found them of some high end cord are needed which gave very nice results and could not replace with cheaper cord.
The Ansuz active plug ins gave what you describe of the qsine and wave. I coyls use 2 at most and openess starts to thin out the mids. Are the new Nordost plug ins similar in effect?
I have have them scattered around, even on other power phase lines to good effect.
Recently added a good number of purons, also work well on lines elsewhere, no neccessarily at the plug to fridges, but i believe they had the same effect elsewhere, probably the same phase.
The purons are very different to the addpowrs, Ansuz plugins and found them more like the effect of the later HFC helix + plugins.
So was curious about the nordost. Do the nordost work more in the music room environment or anywhere around? I did not try the qv2.