A very good film until about half way, but the second half tested credibility. In fact by the end of it I felt I had been taken for a ride. On the other hand From Dusk Till Dawn was the same sort of film (in as much as it is a film of two very different halves) and it's now a cult!
I really enjoyed it, especially with the twist midway through that completely turns the film on its head. Ok, you feel a little cheated by it but its a great idea and the film pulls it off really well.
I wasn't expecting much from it when I originally loaded it up, but enjoyed it immensely.
I actually thought the movie was better after the twist. Before that, it was a by-the-numbers generic thriller with some pretty wooden acting. But the twist turned it from a throwaway rental into a half-decent film. It's nowhere near great cinema, but it's a fun ride.
EDIT: The very ending, however, went on 20 seconds too long.
Saw it in the states when it first came out. As noted above, I felt the ending was a bit of a let down but still liked the film and have just received my "Special Edition" copy from DVD Soon which has an alternative ending and perhaps a better cover(the disc has he same picture as that on the standard cover if this interests you at all). Not bothered whether ending is better or not as I still like the film. I believe this edition is RCE but I have played the first few minutes and no problem. The sound effects seem very good with all that "rain" splashing around the room.