This question may be moot now. Oracle EOL'd FS1 and RIF'd most of the FS1 staff a while ago. While both ZFS (now ZFS7) and FS1 are/were unified storage systems, ZFS is primarily NAS; FS1 was primarily SAN with some QoS and multi-tenancy features and such.
Flash storage is a data storage technology that delivers high-speed, programmable memory. It is called flash storage because of the speed at which it writes data and performs input/output (I/O) operations.
This question may be moot now. Oracle EOL'd FS1 and RIF'd most of the FS1 staff a while ago. While both ZFS (now ZFS7) and FS1 are/were unified storage systems, ZFS is primarily NAS; FS1 was primarily SAN with some QoS and multi-tenancy features and such.