I like my current LCD-2 much better than the one I had a couple years ago. Amp has stayed the same, only difference is dac. Seems to have better highs with more air and a bit wider and deeper soundstage, they also sound faster and the bass hits much harder than my older pair. I would become bored listening to the first pair I had but not now, these things are aggressive and fun. Both were rev. 2 btw with the metal connectors.
I favored the HE-500 over the first pair but now it's no contest... my current LCD-2 best it in every category.