I guess it depends on what you value most: the headphone or the amplifier. In my case there is no question about that: the amplifier. It is a custom unique model built for me by a deceased builder. A very special amplifier. The headphones can be bought again but the amplifier cannot.I'm kind of baffled by this. I would never disconnect the cable from the headphone when I could instead disconnect the 4-pin XLR jack from the amp.
PS. The XLR jack has the locking mechanism.