Sonnet Fusion F2QR

Anyone with experience with Sonnet Fusion F2QR? I have one that works well, with two 500GB HDDs seen as a single 1TB volume RAID 0 that boots using FW800. But I have been unable to get a second to work: two HDDs are seen separately by Disk Utility and I can’t figure out how to get the F2QR to combine them as a single volume. This is in Snow Leopard in a MacPro3,1.