There's no difference between the 2.5" and the 3.5" externals, just the physical size of the HD inside and that of course dictates the size of the external HD unit itself. As for the best company, after using many different brands the top 2 are Seagate and Western Digital (WD). I've encountered far fewer technical issues and defects while using Seagate drives, both in the work field and in my personal home uses and travels.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.