Very straightforward and still gripping - I felt that the film's pacing is very even throughout the very different chapters, which gave it a somewhat documentary or even "slice of life" feeling. Bogart goes through an interesting transformation although sometimes he was a little bit over the top, I thought. Walter Huston is amazing to watch and although his character doesn't change a lot through the movie he adds an amazing depth and reality to the prospector he's portraying.
When Bogart's character is killed I was amazed by the situation before - the bandits didn't seem really dangerous (unless to the deranged mind of Bogart's character, of course) they were portrayed amazingly stupid and simple. The ending was predictable but still quite amazing.