It is true that sometimes it takes a bit of adjustment to get that right spot, both for sound and for comfort.
After two years or so with these phones, and finding that yes, I do really like the headphones, the temptation is to hit the high end. But where to go next? HD800? Audeze? Oppo PM-1?
Apart from a very few minutes experience of the LCD-2, I have no experience of any of those as yet.
And, sometimes, when I put on the AD900s and turn on the music, I get that lovely but rare-among-audiophiles sensation: I don't feel like upgrading, just enjoying what I have some more :)
I bought the TLC-1 (I think of it as Tender, Loving Care!) because I got a fascination with it, I have never used separate pre/power amps for the hifi, and and made my desktop system fit around it. Of course I since discovered that lots of people have thought of using a pre-amp for switching and volume control in a PC-based system. New to me only.