@illitirit, I also have a LCD-2f, the bass on the TH-600 IMO is really fun, the LCD-2f can be to laid back for some genre of music that I listen to.
Lower bass: LCD2
Bass quantity: TH-600, but goes low enough for me that I don't feel like I'm missing something
Mids: smoother on LCD2, more forward and lively on TH-600
Highs: Crisp and extended on TH-600, sometimes can be a little bright, just about right on LCD2 for me, does nothing wrong.
Sound Stage: pretty good on TH-600 but slightly better on LCD2
These are very different sound signatures and you will easily be able to tell them apart. Above is my impressions using UD-301 DAC and Project Ember (12AXX7 Telefunken, low impedance for LCD2 and mid impedance for TH-600). If you want a fun headphone that you can rock with I'd take the TH-600, if you want a smooth better balanced sound then the LCD2 is the better choice.
Note that there is a noticeable difference between the fazor and non-fazor versions of the LCD-2, I'm one of those that like the fazor version better, I like the mids better with the fazor.
Good luck!