Hi there malice7,
It's great that you've decided to go with WD.
The thing is that, you will not really experience any noticeable performance difference between the two.
As you already know, WD My Passport has more features than WD Elements. Another thing is that WD My Passport has longer limited warranty compared to WD Elements.(3 years vs 1 year)
Let me know in case you have some more questions,
D_Know_WD