@BF1983
If the SHP9000 you referred is faheem's then its completely wrong. I had used his 9000, and it has something seriously wrong, i mean its cone seems to be damaged or something. It stutters too much on bass and detailing was almost gone completely. Try to listed another set, maybe u will change ur attitude towards SHP altogether.
SHP 8900: good detailing with tight bass, but not very powerful either. But the bass quality and quantity is better than AD700. Is harder to drive than AD700, HD201, RX900 etc. Needs proper amping. Havnt heard HD 555 or HD 595, but heard from other guys that the 8900 is somewhat sounding like HD 595, but 595 has lot better earcups, comfort and is lightweight.
AD700: Great soundstage. One of the best soundstage HP in sub 10k. Detailing too is good, but great. Bass is week and quality is OK, but hey its an open dynamic HP. Suited for classics only. Also good for gaming like CS where it seems to create a virtual positional audio experience, but no way its surround effect like Roccat Kave. Amping is not necessary, even clip+ is able to drive it properly.
Both are really comfortable to wear, and can be used for long hours. Ad700 feels lighter. Both are worth their price. For gaming and movies with bass, 8900 will be better, but make sure u have an amp, atleast an E5.
AD700 needs really good source for its amazing soundstage to surface. Might not sound that well on onboard or entry level soundcards.