Awful.
The other 4 purge movies are just good, scary, horror fun. This is nothing but a huge political statement about illegal immigration and racism. The people I went with and friends that have seen it (all identifying from different political parties) agree that it was extremely political. There's random references to politicians and Native American's that were unnecessary. Possibly the most disappointed I've been in a movie.
MINOR SPOILER FOR ENDING
The last half hour was just to show Americans what it's like for Mexicans that have to run from the cartel. It did not work. Whoever made this does not like America and it's disappointing that an American film company would produce this.