Assume you want wired, analog, proper on-ear like Koss Porta-Pro. Are you going to use equalization? What is the application? How important is sound quality compared to things like comfort. Do you want to hear background sound?
I use Koss headphones (KSC35, KSC25, Porta-Pro, KPH30i) for cycling, walking, and working out because they tolerate sweat and I can hear cars with them on. Sound is decent, but probably not as good as your (and my) AT M50. I use Bose QC35ii a lot when I don't want a cord and don't want to hear noise. I will switch to QC45 after Amir tests them. I am guessing they are about the same with better battery and connector, and possible some other small surprises.