What do you see as the benefits of high-performance NAS technology?
In my mind, the key benefit of high-performance NAS is steady performance across a wide range of operating conditions. For example, if you're replicating, doing multiple site replications or doing snapshots, all of those activities have an impact on standard NAS architectures (even if the vendor calls it high-performance). Every time you do a snapshot or a block-level replication or a file system scan, it has some impact on the device's ability to service end-user requests.
For me, a true high-performance NAS device is a non-bell-curve technology -- there's no spike up in performance nor a dramatic drop in performance. You get a level, constant flow of information to your end users and applications.
Expect to see some technology changes in high-performance NAS over the next three months, including in-line data deduplication and in-line compression, which you cannot get today while still maintaining high performance. Some NAS vendors claim those capabilities today, but I would not consider their offerings high-performance.