capturing minidv and firewire

[mrkww2000]

any reason why to buy a minidv playback device to capture video to a computer compared to captureing from a canon xl2? If so, what do you recommend?

Also the difference of firewire - 400 and 800. With 800 do you still have to capture at real time or can you capture to a computer at a faster speed?

Thanks in advance.
Kurt