Oh, can you (run vertical spinners), Ill be running it then... The mounting has now been strengthened with an solid 8mm shaft on the other side of the motor shaft (8mm as-well). This is enough as it is supported on both sides and because the spinner doesnt have THAT much energy.
Even if the WHOLE weapon assembly came off (I bet all of you a tenner that it wont ), I dont think it would cause a serious threat to the arena or anyone around.