Tombstone was a different beast, and that sort of overshadows this, given that one tries to be more accurate and the other goes for entertainment.
Take Wyatt Earp as a biopic and it is a superb and fair film. Compare it to Tombstone which was more of a Western and it's lacking the flair.
However, it ends abruptly, and it is miscast. Cosner (and i am a fan) doesn't really make a good Earp. Dennis Quaid who I am also a fan of, doesn't make a good Doc. This was 1994, in the 80s I might have a different opinion, but they both looked a bit old for their characters and the time.
However, I did like the parts of the Earp story that they added, I did lament the absence of Luke Short (who needs his own movie), and I liked how the story unfolded.
For a biopic, it is an epic. It just got compared to a western.