Peter,
Thanks for watching my tutorials, I appreciate that.
All of the tech guys that I've talked to recommend that you only have your applications on your boot/systems drive. With the Mac Pro you have extra slots for internal Serial ATA drive that are dirt cheap know. I bought a 1TB drive for like 200 bucks not to long ago. I would recommend that you buy one and put all of your project files, art work and music on it. I would put my capture scratch on the external drive. I think that is a ideal setup.
That being said, I'm not an engineer but under your current set up I would save everything to the Raid 5. If a drive goes out you still have your stuff. Plus your applications doesn't have to compete with your project files and stuff.
Hope this helps.
Stephen Smith
Lone Peak Productions
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