I'm looking into replacing or adding on to an existing EMC AX4 Clariion iSCSI with about 18 TB of raw storage in 36 SAS disks. One tray was purchased about a year ago with 12 600GB 15k RPM disks, and the rest are 400 GB 10k rpm. It's currently configured with the best practice setup of the time with only 11 TB of usable space for use with VMWare. I was wondering what experiences people had with other RAID systems.
I've currently researched a few systems but have no real world experience with the newest RAID models. How do the following compare?
EMC VNX and EMC VNXe - block based storage should be faster than AX4, but very expensive. The VNXe is about half the price of the VNX and may be a better solution for this company. VNX with a single tray of 12 600GB SAS disks is around $40k. The VNXe should be half that price. If I go this route, I can't replace the system all at once.
NetApp - file based RAID may not be best for VMWare because of Vranger backup in use? I Haven't checked yet on their iSCSI models, if they have them.
Stonefly - they seem to be much cheaper for the space, but I have no idea about them. How do these compare to EMC? Are they any good? $15k for 32 TB. It's unclear from their marketing material whether the 32 TB is SATA, but that would be my guess.
Nimble. These supposedly could be much faster than anything out there, short of an expensive full SSD RAID. They use an arrangement of 12 cheap SATAs and 4 640 GB SSDs as cache. They seem expensive for the cheap SATA. 36 TB for ~$66k. 24 TB for $60k. 12 TB for ~$40k. This seems to be most cost effective with 36 TB Raw storage, since 3 TB SATA drives are not much more than 2 TB or 1 TB Sata drives.
The marketing demos I've seen do look good, but they aren't quite enough to show real world operation. It would be great if anyone with experience in any of the above could tell me how they perform in comparison to the AX4 and/or each other. If there are any other RAID systems that people have used with Vmware, and had good experiences with, I'd like to know too. Should I follow in the footsteps of the previous admin and continue with EMC, or change course for something that might be possibly better?