I liked the film. It's done on a modest budget, but it's wonderfully gritty and authentic (with one quibble) and beautifully photographed. Good performances, I thought. The story is logical, the escalating problems caused by the journalist's idiocy (ya wanna smack him). I especially liked the - for once! - intelligent attention paid to alien biology. A credible life-cycle is presented with reasonable explanation of the aliens' violent outbursts. Even the attraction to light, especially flickery light like a TV's, had a suggested reason. I love intelligent science fiction. Aliens are filmed with effective restraint, which works so much better than the look!-another-special-effect! style of some Big films. Monsters is good. Late in the film comes the first, last, and rather beautiful image of the monsters.
The quibble? It was shot in Costa Rico, Mexico, and Galveston, Texas - after it was devastated by hurricane Ike. After getting such a good grade in Xenobiology (at least surface-believable - give it an A), Monsters totally flunked North American Geography. Sorry, no jungles or mesoamerican pyramids near the Mexico/U.S. border. Even if there were, topography wouldn't so suddenly switch to coastal sand flat, just steps beyond the protecto-wall. Nevertheless, it was a personal thrill to see Ike-damaged Galveston. Good to see that mess useful to somebody: it made very convincing alien damage.
Somehow that seems to sum up this film for me - the clever use of difficult circumstances to create something rather special.
Monsters film still courtesy of The Brag