You should definitely enable the disk cache.
The rationale is that ZFS assumes enabled disk cache and so flushes any critical writes (ie: sync write and uberblock rewrite) via appropriate and specific SATA/SAS commands (ATA FLUSH, FUAs, etc).
Leaving the disk cache enabled permits to capitalize on the write-combining capability of modern disks without impact on pool reliability.
This obviously assumes that your disks actually honor the cache flush command, which is the norm for modern (post-2006) disks. In the rare cache your disks lie about cache flushing, then you should disable it.
As additional information, I suggest you reading the zfs_nocacheflush tunable description:
ZFS uses barriers (volatile cache flush commands) to ensure data is
committed to permanent media by devices. This ensures consistent
on-media state for devices where caches are volatile (eg HDDs).