I just finished watching Haywire....
The storyline was a little blah, But I really liked it and will watch it again tonight.
I think Carano was believable in the part she played. As far as her acting? Hell it was her first 'real" acting job and like I said. She was believable and made the fight scenes look more real than any other girl that I've seen in fight scenes.
I don't think it was a waste of time.