I've only seen myself and a few other people play it, so I'm not entirely sure, (hopefully I'll add high scores soon). I think if you are killed by mine bots, you had a good game. Mine bots appear at 100. My favourite strategy is to drive circles around the enemies until they are tightly packed, and then shoot them all at once. Before rocket launchers appear (50), you can probably get away without using your gun at all, and just running them all over. :)