I entered this little one to the Ropecon miniature painting competition this summer. It wasn't a great success, but I guess you might appreciate it on this forum more than those miniature gamers did:
With the exception of the head, which is sculpted from green stuff over a wrecked Gobot head (only parts of the forehead showing the original head), and the scenic base, which is a scrapped toy tank, all parts are taken from the Warhammer 40,000 model Commander O'Shovah:
(Image Copyright Games Workshop)
The legs received the most treatment, as those "chicken legs" didn't fit the image of the Autobot leader. So they were hacked to pieces at the knee and some additional parts added to the lower legs (from a spare weapon, whose barrels were cut to make the exhaust pipes and lights on his shoulders). The arm holding the gun was cut from two places and the joints resculpted with green stuff. The gun itself has received some modifications to better resemble the original OP laser rifle.
The "O'Ptimus" picture in 1:1 scale can be found here. There's little natural light in the picture - the lighting effects have been painted on the figure (so it only works properly when viewed from a particular angle to a natural light source - it was a real pain to eliminate natural light sources when taking this photo) using the non-metallic metal technique (I'm no expert in that, so this was a risky venture). I took several photos of the model when it was primed (pun unintended) black with a strong light source and used those photos as reference when painting on the lighting. I also wrestled with the coloration of the face - should I paint it grey with blue eyes (80's cartoon) or blue with yellow eyes (80's comic)? I finally ended up with a grey face and blue eyes.
I'm quite happy with the end results. I know there are flaws in it, but it's about the best I can do. Hope you enjoy.