At first I didn't know if this was worth reading, as it fairly closely follows the events of the anime. However the translator's notes at the end of every volume provided interesting facts and context I would not have known otherwise, so I kept reading.
There are some key differences in the manga that explore more facets of the characters, changing up the story in some ways while keeping the core events largely the same.
Even if it can seem redundant at times, this manga nailed the landing in the final volume. The ending was genuinely touching, moreso than the rebuild movies. The expanded backstories and thematic relevance of the finale made the whole read worthwhile. As a result I believe this is an excellent addition to the Evangelion canon.