I currently have the (OG) P1, Timeless, and Hook-X so I can't comment on the S12, Dioko, or Muse, but I can say that the competition is very stiff, and someone really wants to win the competition badly... lol
I think Tinhifi has really messed up here. IMO they are trying to duplicate the success that was the (OG) P1 (they have since the P2, then the P1 Plus, and now the P1 Max; all pretty much duds comparatively), and they will never do it. People don't want to hear lower quantities in bass nowadays (like they used to with stuff like the HD600 and the like that had "audiophile" tuning).
With the advent of driver coatings, and planar drivers being shrunken down, people no longer need to be called "bassheads" because it has big bass (or even be ashamed of it). No longer is the bass blurry, and bloated, and takes over the entire sound signature, but now it blends with the rest of the music (even if it IS boosted) and is so much deeper, and fast, and textured sounding than it used to be.
I don't think I have read any good reviews on these. Wonder what they were thinking when they released these? Surely they had to know they sounded bad???? Must be an engineer right out of college (or was home schooled)?!
I am not making any commitments yet, but I think I have found what I was looking for in the Hook-X. They don't do enough wrong to want to upgrade (I don't need the last 5% I think). And I certainly am not paying (again) kilobuck prices for something that might sound better, but not THAT much better. The sweet spot for me seems to have been the mid-tier offerings. I probably won't need to upgrade from the IT-07 either (they are brilliant to my ears). Who knows this may change tomorrow and I may hear something that blows me away even more, but as of today it stands....