I have a few questions. The main question is how is the BBC edition differ from Discovery Channel edition besides the narration? I am used to Sigourney Weaver's narration voice from Discovery Channel so if there is no difference between those, I would get that rather than BBC edition. Also how is the audio mix and the video clarity compare to the broadcasted version? Is the whole series filmed in a film roll or digital?

We have many existing threads on this title. Here's one of them that came up using the search engine.

http://www.avsforum.com/avs-vb/showthread.php?t=956694&highlight=Earth

Use advance search, title search only, use "earth" as the search word. You'll find all the info you need to answer the above and other questions.

Good Luck