I see many contrary opinions here, but my MSR7s sounds absolutely amazing and even so I'm still thinking to upgrade my dac/amp, maybe I can get more, but I don't know. It sounds so clean, it's unbelievable. I use iFi Nano IDSD with foobar and mp3s upscaled to dsd256 (well my music is mostly mp3s, like 20 TB, I don't want to translate that in FLAC files)
I don't recommend for games but for music, oh man.
From a scale from 1 to 100, 1 being the most metallic sound (cold) you can think of, 50 being neutral and 100 being the warmest, I put this headphone between 30 to 40. They sound a little on the metallic sound, you know, on the metallic sound is the true nature of metallic instruments, we as humans like to listen to music to enjoy so we want music without metals ringing in our bones. Almost all studio monitors tries to sound about the same as MSR7s and this is a good thing. I don't know why people say MSR7s has wrong tonality for mixing, for me they are just between cold and neutral, not 100% neutral, but 80% neutrality is there, and 120% away from warm. My LSR305s are neutral for me.
MSR7s don't have a flat frequency response, but that's another story, there is no headphone with flat frequency. Also flequency response means nothing for me. A single bump, even 2db 250hz in a frequency graph, makes that headphone to sound like a different headphone from the original headphone.
MSR7 is very enjoyable even without a flat FR, I don't know why people care about FR. It's like you don't buy a car because you don't like it's color.