There has been a lot of discussion out there as to poor video transfer quality and excessive dirt not yet fully cleaned up in these blu-rays. I did notice on one occasion some dirt left on the picture in one sequence of Star Trek 1 from the conversion process, however, they are minimal. They are still very clean, brightly coloured, and comprising a wonderful, full sound. I believe some of the comments are unfairly critical, but that is all up to individual choice.
I really like the quality of the set itself. All blu-rays are self-contained in their own slim case with a very cool hologram-like picture of one of the main characters on each. These all go into a nice sturdy cardboard slipcase with a further plastic slip case around that. It is a very nice collectors set.
I never had the DVD set of these movies, so I really cannot compare the quality over and against them, however it should be noted that "Star Trek: A Motion Picture" is the original theatrical release and not the Director's Cut. I like the original, so it wasn't a bother for me at all.