I watched this movie some years ago and till now I've rewatched it more than three times. I've even recommended this movie to my mother and family and they liked it as well, especially my mum. :D
The CGI was awesome and especially the green tao-tei monsters looked very real.
I liked the Chinese characters more than the three western ones, especially the female general and the leader of the wall warriors. However I think that all the actors did a good job with their roles.
The plot was quite basic and could be easily guessed but one can't expect some big plot twists from an action movie.
Overall it is a great movie worth rewatching.