the audio technica ATH-M20X are the auratones of headphones. they are bad in an incredibly specific and extremely useful way. i do not recommend listening to any music on these unless you have a business imperative to hear it in the cold light of day
this is the plunger of audio gear. you don't buy a luxury plunger. you don't want to be proud of one. you don't even care which one you have. you just want one to be there when you need it. a pair of these exact headphones should hang next to every piece of audio equipment in existence, the same way that one might hang a fire extinguisher in a commercial kitchen, near the stove, but not too near that you can't get to it if need be. i would put a pair of these headphones into a go-bag
it's really weird. describing these things is really weird. i've listened to $20,000 headphones and appreciated them; my usual go-tos for Serious Listening (rare) are a $250 pair of sennheisers that i generally consider the peak of my particular hearing range; day-to-day, i listen on bluetooth earbuds and wireless headphones, quality takes a backseat to convenience no question. these headphones are worse than all of those, subjectively, but they are not actually bad. they do not have a poor frequency response; they are in fact incredibly Tight and Precise. they do not have bad stereo imaging, yet they have atrocious staging. it sounds like you're listening to music in a closet, but the most acoustically ideal closet ever made.
ATH-M20xBT are my daily headphones, and have been for two years now. I listen to heaps of music from em. I like the sound signature, but yeah they are very close.