Intensity card live transcoding possibility?

Hello,
Several questions here, so please bear with me!:

- I have been making my first documentary using a Sony Z1 (HDV tape); I also have a Canon HF100 with which I've shot HD footage (AVCHD) onto class 6 cards.
I have a non-intel Power Mac G5 Quad (PCIe), and need to find the best way to ingest the footage into FCP.
Does anyone know if there is any advantage to capturing via HDMI capture card using the camera to play the footage? (as opposed to just using a card reader to ingest the card data, and firewire to transfer the HDV tape playing from the camera)?

- Also, I plan to get a mobile set-up where I can do a live feed into a laptop to bypass compression. I've heard that Mac laptops are not up to the job of live HD aquisition/conversion, but have discovered that PC laptops come as quads (plus 2-3 HDDs) which are more powerful. Is it ok to put a live feed into the HDMI connection which some of these PC's have, or would it still be necessary to use a capture card? If so, would a Matrox mini or Black Magic intensity (in a Magma box) be better?

- I want to transcode to Cineform or Pro Res at the point of live capture; can I do this without FCP on the laptop?

- Would I need to use an external (esata) RAID to process and store these files, or is it ok to RAID the laptop's internal discs instead? (I won't be editing on the laptop, just capturing/transcoding/storing until I can transfer onto my desktop system)

I don't want to have to spend more money on this set-up than I absolutely have to, but I want the best quality possible too...

Help very much appreciated!
Thanks