Well, I tried out Primo Ramk Disk Standard Edition. I made a 8 GB RAM Disk and put all the most heavily used MPQ files on it and used symbolic links on my WoW Data directory.

This include the following

world.MPQ
texture.MPQ
itemtexture.MPQ
model.MPQ

My system has 24 GB and my 10-box setup uses about 13 GB. So with 8 GB dedicated to the RAM Disk, I had plenty of head room for WoW.

Load times were shorter and running around in Org with my 10-box was significantly improved.

I played a battle ground, AV, and at the start it went very smooth. However, about 1/2 through the game I started getting crazy lag where all 10 clients were freeze up.

I'm not sure if it was the RAM Disk making my system unstable or something unrelated.

I will do a few more tests to confirm.