Just having a break from watching it for the first time on Blu-Ray. I'm about half way through and my opinions are, maybe, quite biased by having just had a couple of glasses of wine and being slightly buzzed. It's an excellent action film ; great direction, camera angles, cinematography, pacing. Basically one long action scene and so far it's kicking arse.
Petrol is quite unstable and would deteriorate rapidly, and it is extremely unlikely that enough would be available to run vehicles of the size and weight seen in the film but, after all, it is fantasy.