RAID10 (mdraid+lvm+xfs (never use lvm raid) or btrfs) is way more convenient in terms of rebuild speed, simplicity, performance, and also supports online growing and online shrinking (btrfs only). If there are any failures in a batch, it signals the need for possible proactive replacement. The biggest predictor Google found that SMART doesn't catch is slightly elevated temperatures. ZoL (as opposed to SmartOS/Solaris ZFS) bit me before (array permanently unmountable on good drives) and there was absolutely zero (0) support and they were shameless about it.