The character is just so interesting and just so cool to me. I loved fighting against him in "Turtles in Time" one of my favorite boss fights, supposedly possessing all of the ninjutsu moves of the turtles with advance robotic tech. Although the 2003 version of the Ninja Turtles didn't re-introduce Metalhead, they did design some kind of Turtle-bot that even posses all of the Turtles weapons.
You have other interesting characters that portray this kind of thing like Metal Sonic and even Mecha Naruto. I mean imagine having a robotic version of yourself. What would it look like? What would it do? Maybe one day I'll create a Mecha/Robo "Sprintz".