Good to hear you enjoy your headphone.
Anyway, If you ever have the oppertunity to try a dac/amp or money to spend on one, do it. It might amaze you that they can sound even better.
Had same experience myself (with other headphones); thought they where all I needed (and they where since I didn't knew better), until I tried them with a dac/amp. Blew me away what such improvement can make a difference.
I believe it. It's on my wishlist but it'll be some time. I'm not sure if I should just get a new soundcard with a headphone amp or a desktop one. But they do sound fantastic even without one.