A must buy for fans of the series!
This is a huge upgrade from the DVD set, which I also own. This BluRay version is in 24P, which gives it a film like look when compared to the DVD version. As others have noted, some of the night scenes appear grainy. That is only because of the high speed film stock used in night shooting. The grain is definitely within acceptable range and not bothersome. The daylight scenes are pretty sharp and clear.
As to the sound quality, the menu allows you to select 2 channel or surround. I chose the two channel (Dolby 2.0), and have not noticed any issues with sound. In fact, I would say the clarity of sound is a huge improvement over the DVD version.
All in all, watching the BluRay version is a whole new experience. It is also a much better experience.
Verified purchase: YesCondition: New