Jason,
You are right on the money. We are in fact looking at a Dell MD3600i configured with 6 x 600gb 15k SAS drives (Not optimum I know, on the number of Disks) configured for RAID 10. This unit comes in at $10k or so. For almost the same price we can get another PE R510 configured with 12 x 300GB 15k SAS drives, double the memory and a little jump in processor power over what we currently have now.
I realize we have much greater expansion options with a MD3600i but we would still have to increase our current servers 64gb of memory to keep up with planned growth. This would add additional $$ to the cost.
Going with the additional R510 would allow us to run at least double our current number of VDI's to about 45 or so if I am correct on IOPS.
But I am open to ideas.
Thanks again,
M