Email: Feature vs. benefit [EKW]

I'd like to have a discussion with you about the semantics of features vs. benefits, because while I understand the words, I don't feel I've ever "clicked over" into becoming a native conversant in benefitese. For instance, we could discuss the semantic differences in the following what-it-is (or what-it-does) vs what-it-gives-you (or what-you-get) sentences:

+ Able to leap tall buildings in a single bound (feature)
+ Saves your life even if you are trapped atop a tall building (benefit)
+ Able to save your life even if you are trapped atop a tall building (feature or benefit?)
+ Enables your life to be saved even if you are trapped atop a tall building (feature or benefit?)