The original Legend Of The Galactic Heroes anime series (1988-1997) is great, one of the best space operas out there. However, some people believe that the first two episodes of the series are the weakest part of the story, as they may feel a bit rushed and arguably don't do the best job at introducing the main characters and conflicts.
Personally, I still don't think that those episodes were bad, although after watching this movie, I'd highly recommend everyone to watch this full-feature instead of the first two episodes of the OVA, be it your first viewing or a rewatch.
What we have here is basically an extended version of the first two episodes, with the first half of the movie being more of a prequel to the original story. It does a very good job at introducing the viewers to the world of LoGH, including its' main characters and their struggles. I believe that it develops the first act of the story in a better way than the first two episodes of the original series, with more details and character exploration, updated quality of artstyle and better cinematography.
To sum up, this movie works really well, both as a prequel and as an reimagined, arguably slightly superior rearrangement of the first two episodes.
It should be noted, however, that this is not the first spin off-prequel to the series. There is also another 1 hour-long feature, called "My Conquest Is The Sea Of Stars", which takes place even before this movie. I'd say that it's also good. Wouldn't call it a must watch, but it is still a pretty good alternative introduction to the series. I believe that you can get started with any of these two movies.
