The one that appeals if I could afford it is the Netgear Storage Central box, which comes with 2 x seagate 250gb for £180 inc VAT (in the current Misco flyer), or without drives for £70, and can allegedly hold up to 2 x 800gb. Anyone know how that one formats its disks? It's some sort of RAID controller, that's all I know. They don't say it's Mac compatible, though it's hard to imagine how it wouldn't be accessible since it's a network drive.
http://www.misco.co.uk/productinformation/~104256~WW~/index.htm
Apologies for wasting everyone's time with this, but I'm anxious to avoid mistakes.