I have heard that SSD drives need to be powered up occasionally (not sure of frequency) as that can loose their memory capability if not powered up. Thus the standard mechanical HDD are best for external back up drives as you can powert them up after any lenght of time and the info will still be there.

Another Lesson Learnt - Never leave your camera bag open(unzipped)
I did ONCE ONLY when i left it on the dining room table after rushing out to take a pic.
My wife walked in and romoved the bag off the table and BOOM my nikon 70.-300 lens fell out omto the tiled floor and no more focusing. Fortunatly we have a camera repair shop in Durban RSA call Camera Clinic (Been around since before i bought my Minolta SRT 101) we repaired it at a cost of R3500. Expensive Leasson Learnt

I would recommend a monitor with at least a resolution of 1920 x 1080

If you are using Nikon Transfer you can save to 2 hard drives simultaneously (internal and/or external) when transferring your photos from your camera or card.