Hi there,
I hope to give you some insight on perhaps some of your issues.
1. RAID 5? This is not a suggested RAID set for VDI unless you have a ton of spindles (20+ minimum)
2. SATA? You are only getting 80 IOPS out of a SATA drive on the upper end vs. 170+ on a SAS 15K Drive
3. Network - how do you have your network interfaces broken out? 2 Virtual Machines / 1 Managment / 1 vMotion?
Remember, VDI is about 70%(80%) write and 30%(20%) read in terms of your I/O calculation. How many spindles do you have in your RAID set?
More information would be great to help you out even further.
I speak from experience, we made some pretty serious errors when rolling out our 50 seat View 4.6. I asked a lot fo questions way to late, but I listened, followed the recommendations and today we have a successful VDI infrastructure that is constantly improving.
Cheers!
TheVirtualGuy