When it comes to theatrical versions, Harmy's Despecialized Editions are so much better looking than any other version that I can't believe there's any debate about it. We're not talking a small difference here; put the other versions side by side and the superiority of Harmy's picture quality sticks out like a sore thumb. I'm a fan of dark_jedi and I am eagerly keeping an eye out for his next release, but until then I don't think there's really a contest here.

As for DVD covers and labels, both Harmy and dark_jedi have very nice ones for their releases. Adywan does too for that matter.

EDIT: All that stuff above was me running my mouth when I didn't know nearly as much as I know now about the differences between different preservation projects and the source material used by them. I still love Harmy's editions, but nowadays I would speak in a more balanced way when comparing his editions to others.