I think that when reviewing this movie you have to look at it for what it is. There is clearly no way this is going to be an Oscar worthy performance right from the onset, however what it does provide is a mildly entertaining action film which is based around a familiar, albeit untold storyline.
The acting is not as terrible as I had expected and is probably on average with what most movies in this genre put out. As for the plot I found it fairly obvious to tell what was going to happen and as a result I wasn't really "expecting" anything to happen that didn't. Filming, editing and the technical aspects are all on par with the budget and platform of the movie and were admittedly a little better than I had expected.
To sum it up, do not go into this film with the mindset that it will be the new Rambo or other such thing - otherwise you will be sorely disappointed. Yet it is by far nowhere near the worst movie I have ever seen. I was in the right mood for a good old fashioned beat-down style action movie and this delivered fairly well - would I watch it again? Probably not, but we will see when I get in that mood again.