He makes a good point. Yesterday I was playing multiplayer (I took my time finishing all of the challenges in the campaign, which I enjoyed very much) on the New Sobek City map and as I mostly play Engineer I hopped into a Mobile Anti-Air Tank and it was a thrill.
It paints aircraft really quickly and jets have to fly pretty high to avoid the tank. Helicopters, on the other hand, are easy prey to the anti-air tank.
You fire your first shot after they're painted to get them to pop their chaff. But the tank's second shot is ready before their chaff comes up again and you'll knock them right out of the air! I didn't even have to leave home base and I could still control about half of a large map.
Revenge!