I have never owned a pair of good headphones. I don't think I've even listened to a really good set, though I am curious. In my mind it'd be very hard for me to like them nearly as much as my speaker system. Largely because I don't imagine you'd feel the bass. Plus imaging and soundstage and stuff.
Forgive my rudimentary comments. Like I said, I have no real experience. I'd love the opportunity to give a listen to a few and be proven wrong.
I have a pair of Hifi Man 400i cans.
When my mother-n-law lived with us, I couldn't play my regular system much because of her work/sleep schedule. I had a $20 pr of Sony cans that I used for cutting the yard, etc. so I started using those with my laptop just to get back in touch with my music on a semi regular basis.
I'd started store demoing higher end cans, B&W, Sennheiser, Oppo, plus some of the more commercial brands like Sol, Beats, etc. I noticed a difference, but never bought anything. I think it was 2 yrs ago...Hifi Man was running a promo price for Xmas on Amazon for these cans...reg $499 on sale for $299 so I thought that was a good time to buy.
Where I notice and immediate difference from the Sonys....bigger sound stage more detail. Once I added the DAC/headphone amp...the clarity, details, bass were at another level entirely, really made me get back into my music again on a daily basis.
That said, I've listened to cans that are double the price of mine (at reg price)...I heard a little bit more of everything, namely bass improvement, but imo you reach a point of depreciating returns pretty quickly going from a $500 pr to $1,000 pr of headphones.
Now that mother-n-law has bought her own place and move out, I've been listening and rebuilding my home system a lot more. No, when I'm able to crank it up (60-65 on the Marantz) the headphones can't replace that level of listening. But I still use my headphones on a regular basis...especially when I'm in discovery mode on youtube.