Great insight, as I'm considering them but I listen mostly to rock/metal stuff produced in the digital era (porcupine tree, dire straits, opeth, Steven Wilson, Devin Townsend, Plini, etc).Yup, nailed it - classic rock, prog rock, rock/fusion - all great. Boston, Journey, early Genesis, Camel, etc - ZMF does really well with this material. I'd say roughly most rock/metal after 1984, when production gets digital, then ZMF fall short.
Is it there any relaxed/warm open-back headphone you suggest for this music? I'm looking for a complementary one for my Arya SE, for when I don't want to actively listen to the music.