Hey KKwong !!
I'm a noobie here but I come from a very nice headphone community. Please check Head-Fi
for ANY thing about headphone listening. Do some search there about quality, applications, amplification etc.
littledog asked you the key question. Please let us know.
I've seen some articles on Stereophile recordings and they used Senn HD 600 for tracking.
I own one and it is very good. I use a Berning micro-ZOLT tube amp to drive it. HD600, HD650 and mainly AKG K1k are difficult to drive headphones. Think about a good amp for then.
As far as I know, in terms of quality and not in terms of recording, this is my opinion:
1) MDR R10 - nothing bad for a US 4000,00 headphone.
2) OMEGA II
3) AKG k1K AND HD 650
4) Grado RS1 and HD 600
EDIT: The only headphones I have used here are the HD600 and AKG K1K. My opinion on the others is based in many "head-fiers" opinions. Check there...for your sanity...