I used this in the past among other things. Ended up using SoftRAID before dumping the iMac with Thunderbolt disk enclosure, now just using Linux with ZFS. See

I used this in the past among other things. Ended up using SoftRAID before dumping the iMac with Thunderbolt disk enclosure, now just using Linux with ZFS. Seems like it’s improved quite a bit but unfortunately can’t find many good external enclosure options that aren’t overpriced.