I wouldn't boot with a big slow 3TB sata, no matter if it's in RAID or not.
SSD in RAID is another thing, but the transfer rate of a good SSD will always be twice as much as a 3TB sata, even if they make it go 10K rpm.
On the Amiga side, why would you mount a 2TB drive into any Amiga ?
If you manage to get a 40GB ide drive full, I'd like to see with what, and only Amiga programs, games and tools.
No mp3's, video files or photos, that doesn't count.