right. thanks for the re: indeed fw800 is not the way to go.
you can use fw800 - in the end you get what you pay for.
there isnt much mystery to this.

you pay for performance.

I have tested fw400 and fw800 with raptor drives using GTech cases.
http://www.g-raid.com/
--on my intel mac mini, and intel imac- this is the fastest setup you can get.

And of course it works. just not quite as well as scsi- with content the way people have normally used it.

if you need an answer for yourself - you have to test it for yourself - and see whether the results are acceptable for your requirements - at the price you want to pay.