Maged,
I would recommend you make some posts at www.audioforums.com under their PC soundcard
section. There seems to be a gold mine of
information there.
BTW, there is supposedly a whole batch of
firewire interfaces like the Presonus coming
out in the near future. One of them is
the M-audio "Firewire 410"(which will list for $499.00 USD).