MapleDog:Adding
I belive there is a huge plot hole in this movie,how stupid can these prisoners be,they are given cars with weapons including missiles and stuff,so why aren't they using it to blow up the door and get the F out? 
It turns out that the prison angle was ok. But the original concept for the remake was to have an around the world race, which I think was a better idea.
It had many things that made no sense even for a modern action movie, and there was no real story, little characterization, and not much sense of a race, just car-combat. Anderson did a poor job writing, and directed it as though he was anxious to get the movie over with and move on to the next paycheck. But there was some good fighting, and of course sexy babes (trivia: most of the women you see getting off the bus in the commercial are sexy stunt women playing the navigators).
It was a typical action movie, like any other made these last few years. Only the setting and actors change. Think of it as harmless mayhem and it is worth seeing.
But to answer Maple's question, the warden's control tower staff can shut off the weapons electronically, plus the guard towers are fortified against the car's weapons, the guard towers have bigger weapons, there are helicopters with anti-tank weapons, and the only entrance/exit to the island prison is one causeway that is guarded at both ends. So the lack of escape attempts is one of the few things in the film that makes sense.