Great review. One thing I noted from another reviewer's video is that you can get the NAS into the UEFI setup by SSHing in and mounting the EFI partition of the preinstalled UGOS SSD, and then rename the EFI folder to something else so the UEFI BIOS doesn't detect it as a bootable drive. Once you reboot you'll automatically be dropped into the setup or any other bootable device you have attached. This seems to resolve the ambiguity in UGREEN's statement about installing a different OS since you don't need to disassemble the NAS and break the warranty sticker, and it's completely reversible if you don't wipe the UGOS SSD.