Italy Medusa Blu-ray is the 4K resto but boosted contrast and colours. Still probably better than Criterion

France Pathé Blu-ray is the 4K resto and best encoding

Arrow 4K Blu-ray

Arrow 4K Blu-ray

Arrow 4K Blu-ray

Arrow 4K Blu-ray is is a bit stronger than the very good Blue Underground The differences in the body of the film are negligible, but Arrow does have all three main credit sequences (Zombi 2, Zombie Flesh Eaters, and Zombie) that play in 4K via seamless branching. They also un-stabilized the handheld shot in the Zombie closing credits that Blue Underground had stabilized when they added new digital titles. It's back to looking properly handheld.

Arrow 4K Blu-ray > Blue Underground 4K Blu-ray, "has the original Italy mono - think someone said earlier that the Blue Underground was a downmix on that track and the Arrow is corrected"

Cohen Blu-ray

Cohen Blu-ray is the best with the least amount of DNR or sharpening among Germany StudioCanal, Britain MoC and France Gaumont. Even though Cohen doesn't have the best encoding, it's definitely the most superior release. See caps-a-holics caps

Cauldron/Arrow 4K Blu-ray

Cauldron/Arrow 4K Blu-ray

Warner Archive Blu-ray

Warner Archive Blu-ray

Paramount 4K Blu-ray

Paramount 4K Blu-ray set caveat: inferior encoding on the original cuts of Part III