If you don't have too much stuff, you could probably do ok with mirroring across N+1 (distributed) disks, where N is enough that you're comfortable. Monitor for failure/pre-failure indicators and replace promptly.
When building up initially, make a point of trying to stagger purchases and service entry dates. After that, chances are failures will be staggered as well, so you naturally get staggered service entry dates. You can likely hit better than 5 year time in service if you run until failure, and don't accumulate much additional storage.
But I just did a 5 year replacement, so I dunno. Not a whole lot of work to replace disks that work.
When building up initially, make a point of trying to stagger purchases and service entry dates. After that, chances are failures will be staggered as well, so you naturally get staggered service entry dates. You can likely hit better than 5 year time in service if you run until failure, and don't accumulate much additional storage.
But I just did a 5 year replacement, so I dunno. Not a whole lot of work to replace disks that work.