The Apex Armor is hard and sturdy. It is not damaged by regular weapons. In Episode 13, "Triangulation", Optimus Prime and Dreadwing placed bombs around the Apex Armor used by Starscream, who found the armor in the Antarctic. Starscream fell through exploded ice to the bottom of the sea. Starscream survived. Later on Smokescreen used a Phase shifter to kick Starscream out.
In Episode 6 of Beast Hunters, "Chain of Command", Miko donned the Apex Armor (showing the armor can adjust to suit the size of its wearer) and proceeded to give Starscream and his two Vehicon subordinates a sound thrashing.