ESS chips, opamp, smaller OS, smaller screen...
Still, probably very, very, very good(!), so priced accordingly, but not better.
You Need amp12
The U12T has attained a solid reference-point level for being an "all-in-one" balanced IEM with also tunning "modules", and although you can go higher in resolve, with mest Indigo, EXT, Tralii, Odin, and others(I only listing my most recent heard), they still not perfect tend most to not be as balanced as the U12T, but more about personal choice.
I read kann has a slower and stripped android OS, although it probably performs fine.
Yes, amp12 should be better, and then a moded ex/exnp amp12 is yet another level extra than that as well..
And then will come the new amps...
I see alot of choices&variables ahead.