Stealth kills buildings just as fast as flame tanks, exact same. I and others have tested it.

Third, the flame tank is overated, and so is the stealth. The light tank is underrated.

Flame tanks aren't all that good, they are only really good against buildings and mammoth tanks, stealths just plain suck against good players that know how to drive and use camera view unlike the newbies.

Lights have 200 less armor but cost 200 less then mediums, yet they have much more speed, and barely less firepower so they are the best tank in skilled hands.