Some G.I.Joe figures never got popular because of questionable designs or due to being sold with outlandish vehicles. Some never get a chance due to the order you buy them.
For Grand Slam, I picked the Star Wars Miniatures Human Soldier of Fortune mini. He's got a pretty similar look, with shin armor instead of thigh pads. But close enough.
And for once, he doesn't just look like a repaint of Flash.