It's next to impossible to run over phalanx of 7 vehicles twice in endless mode. What's worse, there is always a FULL SCREEN airstrike. Ah and your airstrike is so slow and can't kill many.
For some reason the "Burst" type skills seem to be rigged - "Throw Burst X" never displays, only a strange "Burst" skill which is not in the tree can be used.