This is being researched and experimented with at this very moment. A couple episodes are currently in the testing phase.

Normally a DVD would win a matchup for PQ, except in rare instances, but there are a lot of problems with the ST DVD releases which evens the playing field.

Paramount jamming 4x45 minute episodes plus extras onto a single layer 4.7gb disc is a major one. This adds in a ton of lossy compression artifacts and degrades the image substantially. By comparison, the LD has 1 episode per disc and there is no compression because its analog (Not without its own downsides though).