Well "those HPs" it has are 85, it has a natural 18 protection, 2 immunities, its inanimate status makes him resist again many spells (also, natural MR 18), and being full equippable and requiring Const9 you should have no problem forging many ways to protect the most of those HPs. Parking it on top of a sieged enemy castle should heal it too by the magical properties of the enemy's lab
Even the Gargoyles and the Golems have the same characteristics and are considered among the best SCs.