I have had the LCD-3 for a month or so. I thought I would give my two cents. Considering this is my seconds post, I don't expect anyone will give it more value than two cents anyway.
I think they are very nice. Definitely the best headphone I have heard. Of course I have only heard LCD-3, SR-507, SE310, PortaPro, LCD-2 (rev1 and rev2), DT770pro, and DT800 (600).
To me the the LCD-3, sounds almost identical to the LCD-2 rev2. I would lie and say that it has so much more detail, etc, but I don't hear it. I do without a question hear a much better soundstage. It is wider and deeper in my opinion. I personally preferred the sound of the rev1 to the rev2 if that helps anyone gauge what type of sound I like. Unfortunately they were giving me some problems and Audeze swapped them for the rev2.
I do not believe that the level of perceived quality increase I am receiving merits the price. However I have them, and I like them better than the LCD-2, so I will keep them. I don't want to take the loss on them.
I may build a TOTL STAX setup in an attempt to consolidate everything down a bit. If I do that, then I may part with the LCD-3 after all.
I read someone who said they did not care for the chrome blocks on the bottom of the headphone. Well, I can say functionally it is a great improvement. It keeps the cables from occasionally jabbing into my shoulders. The new pads are also nicer. I think the brown leather looks nice, but I can not say I love the new wood choice.
Sorry if my thought patterns are a bit disjointed. Lets blame it on me being new. I would say you are welcome to criticize, but I suppose if you plan to do that you were not going to wait for my permission.