I had the LCD-2F for a while before getting the X, and I was surprised at how little the X improved over the 2F. At first. After further listening and A/Bing, I realized that the X is an improvement on nearly all of the technical aspects or sound (things like: driver speed and resolution, soundstage, imaging, etc.), but to my taste didn't have the same magic as the sound signature of the 2F. It works for me because they compliment each other well and I don't feel like the 2F is redundant. But, I could honestly see preferring the 2F over the X. I could even understand thinking they are about the same in terms of technical ability. They're not, but it's damn close. Anyway, my point is: give them some time. What they do really well is fairly subtle and takes some time and comparison to hear. It also depends on the amp pairing as well. Less of a difference between the two on my Black Label, more of a difference on my NFB-28.38. Once you do hear the difference though, it's fairly obvious.
MrSpeakers AEON Flow Closed. Likely the headphone closest to the Harman target response curve that's ever been made.