What are your QT Codecs? Have you thought about soft importing them and that way you only have to bring in proxies on to your framestore.
Draft quality is very usable and it generates fast.
Are you on Linux or Tezro?
Here is the basis for soft-importing. I do this all the time with P2 footage in 2010.
This goes for LINUX: If you are on Tezro it's just a matter of getting an external drive/server mounted.
0. Create a project with proxies at 50% and Draft
This wil create 960x540 images on your framestore. If you need touse less space, then you can go to 40% It wil affect the quality of the proxy images.
1. Compile all of your QT sources onto a USB drive.
2. Mount the drive and got to the IMPORT menu
3. select your aources and at the bottom, choose soft-import and then if you have backburner setup, then you can create proxies in the background. If not you will have to wait for proxy generation on import.
4. Once your clips are imported, you can work in proxy mode. You will still be able to see the High Rez images but they will not play in realtime. The proxies will as they are on your framestore.
5. Work and view in proxies. You can even ender in proxies.
6. When you like what you have, just do a full rez render (normal process)
Here is the breakdown of storage when I work with P2. I can bring in 60 mins of P2 at 1080i and by soft import I only use 12 mins of framestore.
I honestly wouldn't recommend it. Five SATA drives in a RAID 5 config probably won't get you the performance you need, at least not near the performance of an external RAID. Also, think of the heat generated by those 5 drives... Without adequate cooling you are putting additional stress on your system.