I bought this 6TB beast some days ago.
http://www.amazon.com/Book-6TB-Hard-Drive-Backup/dp/B00KU686HI
I have another one of these and so far no problems. I've bought several other External HDDs from Western Digitals and so far only one failed me and made me lose all data. I opt for WD always.
As far as I know you need to format external storage for Xbox, at least Xbox360, for it to work in the console. Then you need to format it back to be of use on PC, the storage device space appears completely occupied when you check on it in PC after formatting for Xbox use.
Maybe it has changed since last time I had to work with a formatted storage device for Xbox360, like Micro giving the system an update or something, maybe it is different for Xbone. Maybe someone can weight on this as well.
Nintendo is selling their IPs to Microsoft and this is true because:
http://gamrconnect.vgchartz.com/thread.php?id=221391&page=1
