The fact that the film version tries to mock the book has been repeated to death, but the point stands that the book is actually interesting with real ideas and cooler sci fi aspects (powered armor), whereas the movie is cheesy and dopey.

I generally agree. I saw this in the theater and my opinion was the same then as it was now. It's a neat ending, but it essentially makes everything you watched for the preceding 2 hours totally irrelevant.

A movie with a great twist ending like the Sixth Sense makes you reevaluate everything you've seen before and view it in a different light. Whereas the Usual Suspects twist ending just says "psych!".

I do think the reveal is cool, though, and the scene of the guys in the criminal lineup is hilarious.

I feel the same. The ghosts the kid sees and the situations, particularly the girl who was murdered by the mother afflicted with Munchausen by Proxy was phenomenally well done.