Well good news and bad news for my final verdict of the Phantom Master 6 after spending more time with it.
The good:
1. The Gun Metal is the best sounding (for me) as it's neutral and does not exaggerate any frequency. It's balanced, clean and clear. Nothing overpowers anything else.
2. The PM6 (with the Gun Metal) sounds almost (98%) identical to my Final Audio VI which costs way more. FYI the Final Audio VI is a single BA and well implemented.
3. The only (slight) difference is that the PM6 has more mid bass and a less recessed mid-range which is always clean and smooth just like the FA VI and sounds more full on the bottom end in the vocal area.
4. The PM6 also has a tad more (tighter) bass and it's quick and fast and never sounds bloated or out of control.
5. What I hear the PM6 do (way) better than the FA VI is (although it needs more volume to match the level of the FA VI) the PM6 can go LOUD and still have complete control and never lose it's sound signature or sound harsh. This is one advantage of multi-drivers to do this without distortion. The FA VI loses control and gets shouty with vocals and treble but it's rare I listen very loudly but others may appreciate this.
The bad news (at least for me) was that I was hoping that the PM6 would be the magical IEM to surpass the Final Audio but it instead it just matches it.
The search continues.
Have you tried the Hunter? It's supposed to sound similar to PM6, just a bit better