Harmy’s point isn’t that it’s better, but definitely more authentic. He’s repeatedly stated that the Despecialized Edition, though put together with love and care and the highest quality sources available, is still a patchwork effort, one whose seams you can easily spot if you’re familiar enough with his process. This might be the GOUT-sourced sandcrawler or X-wings, or–one which sticks out to me and will probably be fixed in the next version–the looping crowd animation when the Falcon blasts out of Mos Eisley because some frames were missing. Team Negative1’s preservation is a straight up, unaltered 35mm print. There were some splices and replacement shots but they’re 1. unnoticeable and 2. from the same definition source.

They’re two different beasts. Harmy’s has sharper image quality for the most part because the vast majority of it is sourced from the official Blu Ray, which in turn was mastered from the original negative, whereas Team Negative1’s preservation comes from a theatrical print which is a couple generations removed from the negative and has more grain and thus slightly less detail–not too much less, though; furthermore, it has scratches, reel change marks and still some dirt. Team Negative1’s version is, however, a more visually consistent work.

EDIT: Harmy, being the one in charge of his own project, put what I was saying much more succinctly.