Lloyd, what my isolated negative experiences re Entreq have demonstrated to me is three things. One, as in all things high end, YMMV. Eg after the initial high of grounding the preamp solely, a second Apollo to my phono stage really didn't work, just making analogue sound muddy. I turned away from this option. Weeks later I changed to my current Soundsmith Straingauge, reluctantly gave grounding lp replay a second go, and blow me down!, grounding really worked. From then on, I quickly added further Apollos to cdp and monoblocks, and got a cumulative impvt. next up is grounding my Zu sub amps when they come back factory-modded w/ground posts.
Two, despite the nay sayers prob thinking the whole thing is a giant placebo effect (in actuality, nothing wrong w/this, placebo actually being a positive facet of human psychology), my negative experience proves I'm not easily led, sheep-like, into a high price scam.
Three, you're prob right that Atlantis cables need to be the upgrade across the board before I consider the Atlantis add-on box - there may be a bottleneck in grounding w/Apollo cables v Atlantis cables, which actually scuppers the effects of the Atlantis box.
My next round of possible grounding is going to commence at the end of the yr, and my debate is whether to go for all-Atlantis cables, consider Entreq product "X" on individual components that you are raving about, or concentrate on grounding the mains/my balanced transformer via Entreq Powerus/Cleanus.