Fantastic movie that always has you guessing

Rating: Null/10 (8 September 2001)

Warning: Spoilers Supreme ahead; if you haven't seen the end of the movie skip this summary completely.
I agree with the people below who say the ending is ridiculously implausible; that the people controlling this, would instead of just ending the game when he thinks he has killed his brother, they go one step further, and lead him to fall hundreds of feet, onto an airbag. There are so many ways he could have died, can you just see someone saying "hmmm, maybe we should just have ended it on the roof, I forgot to take that slight wind into account. Oh well."
What are the odds that of all the places on the roof he could have taken the plunge from, he picks the only spot within two feet either way where he would hit that bag.
And how about the impact on his body of hitting that glass from hundreds of feet up, accelerating every 32 feet. Good thing he hit both the glass and the airbag on his back.
However, I also read in a couple of places that originally he did die and just went splat below; but that test audiences found it too grim an ending, so they changed it.
But I didn't feel cheated, because it just added to the final twist. Even when the girl is pleading with him that his brother is behind the door with a bottle of champagne, you don't really believe her. Besides there are so many things that seemed implausible, from him getting out of that sinking cab, to the seemingly real bullets strafing walls everywhere he runs. And how about that attack dog gnawing at him on the ladder? Was he an actor who knew when to stop biting?
Anyways, you have to suspend some cynicism and just see it as a spectacular prank a man plays on his brother in a last-ditch effort to get him to turn his life around.