Well, RAID-0 is indeed faster. Comparing on Fedora 34 install.

Sata-3 ssd

  • Starts: 1m5s

Ssd into Sata-2 port

  • Starts: 1m9s
  • Shutdown: 30s

Raid-0, 2 SSDs

  • Installation: 6m
  • Initial upgrade: ~10m
  • Starts: 45s
  • Shutdown: 5s