I’m well aware of the whole “How Mac OS X reports drive capacity” thing, but these two labels (identical) are off by 489.32 GB.
Drobo Dashboard 1.6.8 [1.6.27123]
Drobo Firmware 1.3.6 [1.253.25784]
via FireWire 800 to:
MacBook Pro 7,1
Snow Leopard 10.6.4
For clarity, I’ve also attached a screenshot of the volume’s info as seen in Disk Utility.