I think it will be SoTM because
imho Legato is outdated with 16bit,
imho M2Tech has too much feature... and I don't want to pay for a layout that I cannot use in the future,
imho Stello has no PSU only powered by USB,
imho Styleaudio Carat T2 is maybe a cheap alternative here (in this group) and therefore maybe under my expectation,
imho JK MK3 Hiface is not sympatic enough because of the batteries
But AP2 looks nice - the only downside here is the crucial BNC-to-COAX (RCA) adapter when I attach it to the DAC - I feel this connection is too fuzy that way.
So looks like I have narrowed it down to SoTM HD & AP2.