I had some friends come in with newer headphones to compare (one with Audeze) and their amps and I was not impressed. It may be that I am just so used to my phones.
Now, I also own other phones. I currently own four pairs of Bose headphones. One (SoundSport) for running, and three QuietComfort which I bought as new generations were produced. These I used when I travel because DT 990s are 250 Ohm and require a bit of stationary hardware to work.
I also have one pair of Beyerdynamic DT 770 PRO which I bought more recently and use when I need to isolate from environment for some reason.
None of these other headphones are as good as DT 990s IMO.
It also sounds quite detailed in the treble range, but if you listen to something like Sundara you realize the detail doesn't actually exist and it's more like a sharpening filter. Sundara also has replaceable audio cables and of course it's easier to drive.
Not really surprised about this, I have never been particularly impressed by Bose except for their noise canceling.
My dt880's sound great - I bought them after auditioning a lot of different modern headphones.
I have some closed planars as well, but I don't enjoy the closed-in feeling that much.
Beyer is the kind of thing nascent audiophiles liked about 15 years ago because they sounded very detailed, but people are better at measuring now, there are newer competitors like planar magnetics (eg Hifiman), and if you compare them now it's obvious that the detail is fake. It's an artifact called sibilance that just happens to sound good, like vacuum tube distortion.