A point is that larger slower SSDs are cheaper than smaller faster ones.

I mention SSD raid For capacity reasons as opposed to speed. The speed part I can make back up by using a PCI raid controller. I am referring to Raid controllers cards with on board processing.

I'll say I'm jumping the gun a little based on rumors of the up and coming release of the new Mac Pros which are supposed to boast Xeon 5600 6 core chips, USB 3.0, and SATA r3.

As far as audio though, I have never seen a situation where an HD video file didn't drop frames at some point coming from a software based media server. Yes, it's negligible and most people will never notice but it's still not satisfactory for broadcast.