I just saw this thread. I rarely visit the Cable thread these days and mostly hang out on the Amp and Speaker threads. I don’t have experience with the 7N PC9900 which I believe is the top of the line Acrolink cord. However, I do have the older PC9700 and PC8100.
I just love what the Acrolink cords do in my system. I would recommend to try at least one of the Acrolinks in the system. They surely do not sound strident or analytical. Their house sound is rather warm, smooth and full-bodied with a nice airy tube-like glow in the treble. The Acrolink cords made all my cheaper cords sound grainy and harsh in comparison (Supra Lorad, Wireworld Elektra 7 etc.)
The latest PC9900 should be an improvement over the PC8100 and 9700. Based on my positive experiences with the 9700 and 8100, I suspect the 9900 would have a higher chance of bringing satisfaction rather than disappointment.
A note is these Acrolink cords are rather stiff and cannot be bent into a small radius.
Good luck.