The King Gallant Mk. II has 1350 HP and is disabled under 30% health. It has "Heavy Armor" resistance: it can soak small arms fire, shrapnel, and 12.7mm machine guns, and it is immune to Flamethrowers. But it won't last long when faced with heavy explosives or anti-tank weaponry. It has subsystems that have a chance to be disabled by heavy explosives and anti-tank weaponry if hit specifically: Tracks: 30% (Anti-Tank Mines always disable them), Fuel Tank: 40%, Turret/Cannon: 20%. It has Tank Armor. With it, in best case scenario, penetrating projectiles only have a 50% chance of penetrating and doing damage. That chance goes up quickly if the armor is worn or if it is shot from up close, or on the side or rear from a direct angle, or with ammo that has penetration bonuses. It takes 135 Basic Materials to fully repair it from 1% to 100% health with a Hammer. Its health, subsystems, and Tank Armor can be instantly repaired at a Garage for 100 Basic Materials.
The King Gallant Mk. II is an effective vehicle that is decent at dispatching infantry, light structures, and light vehicles. Its heavy armor and rotating 30mm turret give it an advantage over early-game vehicles such as Armored Cars, Tankettes, and potentially Half-Tracks. These vehicles might not be able to effectively destroy the Scout Tank, though other mid-game equipment can overwhelm it if not properly supported.
30mm ammunition does decent damage against heavily armored vehicles, and structures, though it might not be the best tool, especially when there are more powerful equipment that can do the same job, but easier. On the other hand, 30mm is fairly cheap and is a cost-effective round.