i have no idea how vintage telefunken or neumann eq's sound. however i have a studer 900 desk and i love the eq. you can apply pretty extreme settings without getting a 'phasey' sound, the 'air' band is absolutely gorgeous, the mids way less aggressive than on an ssl, and the lows are rocksolid.
i used to work on an ssl g series on a regular basis. with the ssl i found myself patching in every outboard eq i could find in that studio to avoid 'that' sound. with the studer i only wish for an outboard eq when i need to make something sound really edgy and harsh.
the things i don't like about the studer eq is that the boost/cut pot doesn't stop at 0db, which makes it kinda hard to properly reset the eq back to flat. and sometimes i'd like the bands to be a bit wider than they are.