I’ve been using AKG Q701s for well over a decade. They’re hard to drive, but extremely comfortable and the sound quality far surpasses anything under $500. I like that they’re open-ear and breathable - I forget that I have them on. I’ve gotten to the point of buying several backup sets on Ebay any time a good deal pops up, just to make sure I’ll be able to use this same model for the rest of my life in case something happens.
The Q701 model is technically no longer produced, but K702 is identical other than the headband style. They retail around $150.