The SD Knight Gundam is all grown up.
The Full Armour Knight Gundam is a premium figurine (with a corresponding premium price tag) that is replete with intricate mechanical and medieval details both etched and painted onto its shiny-finished armor plating. The figure has many sharp points and edges, all of them capable of drawing blood from careless fingers.
While the figure itself is pretty stable thanks to its die-cast parts, some of the armour tend to fall off with just the slightest touch, which can be extremely annoying. As a Robot Damashii, the Full Armour Knight Gundam is able to easily pull off dynamic poses. However, the die-cast left shoulder joint pops of its plastic socket far too often, exacerbated by the huge shield that is (typically) mounted on the left arm. The ankle guards also just sit there in their sockets and the slightest push will pop them right off. While these issues are not game-breakers, they can be quite annoying.
The massive shield has an "activated mode" gimmick: the outer armour essentially slides open to reveal mechanical detail beneath, ostensibly some sort of beam shield or I-Field or beam cannon. The shield can be tricky to maneuver into place due to its size and bulk.
The die-cast parts within the Full Armour Knight Gundam helps to stabilise the figurine without the help of an action base (although one is included with the set). The die-cast parts also serve to ground the figurine with their weight.
Lastly, The Full Armour Knight Gundam also comes with the Cape bundled with the original Knight Gundam, sans the lance. The Cape gives the figure a different look and feel from the butterfly wings.
The Full Armour Knight Gundam scales nicely with 1/144 model kits and figurines, its tremendous bulk accorded by the heavy armour giving it significant advantages in the height department.