Don't worry, if you didn't like the movie the first time you saw it...see it again so you know what to expect, and it really is great. I thought it was merely decent the first time I saw it (midnight showing), and then I saw it later in the day again b/c I loved the action (story was different), and the 2nd time I saw it, I really appreciated the film as a whole.
The movie in itself was very well made, however. If there are any problems really, it should have to do w/ the story rather than quality...
If I die today, I'm happy how my life turned out