> then the USB protocol isn't as efficient as Firewire...
I don't know about Firewire (yet), but yes, there is a significant overhead for USB transfers. I'm pretty sure Firewire is more efficient in that case.
> and finally USB doesn't support Isochronos transfers
Sure it does. How you think USB soundcards work? (But you're right, the isochronous transfer is a pain in the ass, try to keep sending audio packets every 1ms!).
