Why not make it yourself easy.
I bought a cheap nas like the DNS-323. It is 2 bay and there is an active forum and a simple software hack called funplug which opens the box and runs for example rsync and make a backup of one disk to the other automatically overnight. It is all documented very well, even for non linux techies. You could run SBS on the DNS but it is very slow so i recommend buying a Sheevaplug computer to run SBS.
With this you have a cheap, good performance system which uses in total only 10 watt idle (it allows your disks to spin down).