We just got the one... it seems very stable when my son is operating it but whenever I try I just make it go crazy all over the place often knocking into things and causing it's head to fall off. I can't work a 360 et al type controller to play games either though, so.... when it pauses after rolling around it does wobble like a weeble but it's still very stable all things considered, my son is able to navigate it very smoothly with sudden stops and going around moving obstacles, it really seems neat.