I loved this movie. In my opinion, no one else has managed to do what this guy did. The pace is a little too slow for some people, but it's beautifully shot and the little story there is is solid.
And all for $15,000... Which is really quite incredible. Paranormal Activity cost the same amount, and they barely even left the house. This film takes you all across Mexico with giant fucking aliens! This guy could teach hollywood a lesson or two.
If it was just an alien movie, it would have been generic and boring.
Honestly, I didn't think the love story got in the way too much. Maybe you should just go back to Alien vs Predator?