There really isn't a "best," in my opinion, since different strings may have different strengths for different players and playing styles.
For example, take the case of coated strings, such as Elixirs. They unquestionably last better than plain strings--but that won't matter to a player who routinely changes strings on a weekly basis. (Yes, there are more players who do this than you may think!)
And as for longevity, so for tone, playability, etc.
Perhaps the best demonstration that there isn't a single "best" is the fact that it's not hard to find players who use different strings on different guitars that they own.