I gotta agree with Domokun, not only would it save polys, it would look a lot better. The edges of the cube are indented now where the sides come together inside of smooth like they would be on a cube and the extruded/intruded bits look irregular. Also the green is fine but it should be dark enough to pass for gray or black and the yellow looks odd. I really suggest redo this with Domokun's suggsetions since it would look really nice then. Still not a bad model 3/5