The stuff in the arena was so much better in the movie version. The humor that came from Grandmaster's antics is kind of muted because the timing just can't be the same as the movie. The battle, too, was so much better.
Everything outside of the arena is about the same as in the movie.
All-in-all, again, you might as well just watch the movie.
I also want to mention that apparently only the first three volumes are available in English, so you can't even get the ending. After a long gap, it looks like volume 4 is now available in English. Not sure what caused the delay, but it's available now.