I have 3 2TB drives in a RAID 5 configuration with a separate Boot drive running windows 7 64bit.
The array works fine giving me 4Tb usable. My boot drive is a 300 Gb, split into 3 partitions for multi boot operation. The RAID drive is also recognized by Windows 8 x64 and I have had at one point Vista x64, Windows 7 x32 and Server 2003 accessing the RAID. The problem is that under many operating systems the mediashield utility does not load or work. You can specify rebuild in BIOS, but there is no way of monitoring the rebuild process without the utility, so it may or may not be rebuilding. Since it may take many days to actually rebuild, it would be nice to be able to monitor the process.
I have had the configuration for about 30 months. Make sure that you do NOT let windows update install updates automatically or else the system will reboot and your progress will be lost.
ps: windows 7 x32 and x64 and Windows 8 x64 recognize the array and load the appropriate drivers off the O/S DVD. All others require the driver download from nVidia.