You really need to stop the window licking, go buy several of each & shoot them.
Then change out the trigger springs on the SSA versions to a lighter spring, shoot them again, then come back & wax eloquently upon the magnitude of the perceived or imagined differences, & provide guidance on such & where each version should be used.
And if you really want to do it right, you could also add a heavier trigger spring to the E version just for fun.
MM
MM,
I'm just restating what the maker has said, and I do own 1 SSA, 3 SSA-Es and an SD-E.
Like I said, not going to argue with some anonymous guy that knows more than the manufacturer.
So swap your springs and be well..