1U NAS Server -- baseline storage tier. The device most other systems (hosted games, crypto rigs, client contracts) depend on indirectly, since they all need somewhere to actually put data.
8 disks, 64TB usable, RAIDZ2, 75000 IOPS rating, 16GB cache -- solid general-purpose numbers, no standout specialty in either direction.
No built-in redundancy against a real failure or intrusion (0% built-in redundancy chance, the lowest of the three NAS-category devices) -- pair it with a genuine backup mirror share (see `man nas`) if the data on it actually matters.
A share on this device with real used blocks and no configured backup mirror is exactly the scenario the disaster-recovery system punishes: a hardware fault or a landed intrusion on this NAS wipes that share's data outright, with a wallet activity-log line marking the loss.
Tip: this is the tier to use for low-stakes storage (scratch space, a game server you don't mind losing progress on) and to explicitly NOT use unmirrored for anything a contract's reputation payout depends on.
See also: the Game Systems manual's Data Management section for backup mirrors and disaster recovery.