I never worked with Stonefly before, but what I can see is, that only sata drives are supported,and very large disks ( 500- 1TB disks,that are only 7200 rpm),so I have my doubts about performance...
For applications that need response time ( databases and so) you surely will need fiberchannel disks.
Another issue will be rebuild times in case of disk failure...
rgds,
R.