It's funny, but not funny enough, and exciting, but not exciting enough. The label of sci-fi is only given because aliens have supporting roles. The alien bug that takes possession of a human body is hilarious. This gives a lot of physical comedic relief. The problem with this movie is that it has no climax.
Stuff happens, and then it just sort of ends.
The filmmakers seem to hope that the mere idea of a government agency designed to keep visiting aliens in line would be interesting enough to keep our attention, and so they slack off on mentioning what the plot was. It's almost as though they were carrying on the movie behind our backs. It's hard not to like it, because Smith and Jones have so much charm and charisma. It's just not hilarious. Don't let Eric's cynicism deter you from standing in line to see this film.