I mean, it's OK, I guess. Lots of blood, some acceptable FX, a couple plot twists, and some explosions, but no real "zing" to it. You never get involved enough to care that characters are doing something stupid or dangerous. You don't really care when they die gruesomely. (OK, OK...it's not usually THAT gruesome. The FX are about 50% of what they should be.) This ought to be a roller-coaster ride and it's actually a carousel. The tension ought to build and then release, only to build again. It doesn't.
Now, as far as the whole alien sub-plot. That was just someone thinking that the script wasn't cerebral enough. They were nervous and decided to add a "twist." Bad mistake. It definitely weakened the whole film. (And why do I get the feeling that the writer had just watched "Die Hard"? He/she was probably thinking, "Cool! They weren't terrorists after all. They were just thieves. Hey! I know! In my movie, it won't just be a zombie virus. It will be an alien zombie virus!"
Anyway, save this for late at night, when you don't care if you fall asleep halfway through.
Now, as far as the whole alien sub-plot. That was just someone thinking that the script wasn't cerebral enough. They were nervous and decided to add a "twist." Bad mistake. It definitely weakened the whole film. (And why do I get the feeling that the writer had just watched "Die Hard"? He/she was probably thinking, "Cool! They weren't terrorists after all. They were just thieves. Hey! I know! In my movie, it won't just be a zombie virus. It will be an alien zombie virus!"
Anyway, save this for late at night, when you don't care if you fall asleep halfway through.