>a datacenter machine will be more comfortable running headless than a barebones PC so there won't be any thing popping up on the VGA screen and saying "press any key to continue."

        Foreign configuration(s) found on adapter.
        Press any key to continue or 'C' to load the configuration utility,
        or 'F' to import foreign configuration(s) and continue.
        
        All of the disks from your previous configuration are gone. If this is
        an unexpected message, then please power off your system and check your cables
        to ensure all disks are present.
        Press any key to continue, or 'C' to load the configuration utility.
        
        Entering the configuration utility in this state will result in drive
        configuration changes. Press 'Y' to continue loading the configuration utility
        or please power off your system and check your cables to ensure all disks are
        present and reboot.

But generally speaking, that's more or less true (except for the temperamental LSI based controllers)