Honestly, I'm more interested in them for listening than working on them. I have Ultrasones, ATH-M50x, AKG K240, etc for work, and they all do the job fine. I'm typically not one for using headphones in the mixing process for anything other than a reference check.
I used/loved Stax Lambdas many years ago. They're still here somewhere...
I'm interested in them or Sennheiser HD800s... Internet reviewer rumors seem to say LCD-X is more spacious and open. HD800 is more neutral/accurate/revealing. If used with Sonorworks or other, some of that may resolve. I would like to hear them of course, but that may prove difficult. But a high-quality pair of headphones will last a very long time and be exceptional the entire time. I do find headphones very useful in mixing.
The alternative is upgrading my IEM's. I have 6 driver 64Audio right now. They were replacements for a pair of JH Audio 10 drivers - both custom moulded. The JH Audio sounded a lot better. The 64Audio fit better. The plus is getting better sound every time I play live. The downside is that I don't find IEMs to be as immersive as headphones. Headphones are so much "bigger" sounding. Probably due to sound hitting the pinae - I don't know. The 64Audio are adequate for live. I don't love them though. They don't sound "great" and the JH Audio ones did. More drivers seem to matter a lot.
But the alternate presentation is useful to me. I just haven't decided whether its worth it to go "high". It probably is. I just haven't got there yet.