I need to save 4 TB of my family photos + videos onto two HDDs.
I have the following options
1. Use two 4TB WD 4TB Elements Desktop Hard Drive - USB 3.0 - WDBWLG0040HBK-NESN (These are powered with an external adaptor)
I plan to use two such HDDs so I have a spare if one fails
2. WD 4TB Elements Portable External Hard Drive - USB 3.0 - WDBU6Y0040BBK-WESN (Non Powered only via USB)
I can use two of these to save all data
3. Use 1 Hard disk 4 TB (Powered with adaptor) and a 2nd HDD (4 TB Powered with USB)