He's still posed on my shelf between two SW statues, still brandishing his lightsaber. Aside from some saber slippage (it's basically a cellphone charm), I have not had any problem with him holding a pose and maintaining it, despite me digging books off my shelf, or even repositioning him. The C-clip holds him just fine, and if I want to alter the pose, I take him off the stand, pose him, and put him back on. The surface of the stand is pretty slick, so I've had some issues with it, but I may try balancing him on rougher surfaces where he'll have more traction.
Half the time, the C-clip is barely holding on and he stands fine.