Read the para below, if you want to save atleast $1500 in the event of Hard drive failure.
In the event that you encounter the horrible "hard drive not found" message and you now realize you have a "dead hard drive", and you have a Windows Home Server, Data Recovery via the Restore Computer Wizard will take you about 1 hour, minus the time it takes you to run out to your local computer hardware store to get a new hard drive. The new hard drive that you purchase just has to be at least the same size as the previous drive. Little known fact, if you want to upgrade your current hard drive with a faster larger drive, you can perform the same steps with the Restore Computer Wizard to put your new hard drive in place. Simply run one final backup of your pc, shut down, pull your old drive, install your new hard drive, boot your pc with the Home Computer Restore CD and follow those 6 simple steps to you newer, faster, expanded capacity pc.
Source:→ WHS Blog