I have the same issue. I have used the G-Tech utility to reconfigure to Raid 1. The instructions then lead you to initalize your disk and to follow the clear instructions to do so in Disk Utility. However there are no clear instructions to initialize (my disk is currently not showing on my desktop, FYI). So, I chose Raid Assistant under File and this takes me to a window to change from Raid 0 to Raid 1, but when I select my drive to do so, the Next button is grayed out. I suspect this is not the pathway to take and this is what you mean by hardware versus software RAID devices.
But what DO I have to do to initialize my drive?