Not as an improvement, those look like the harder-than-robochallenge compound wheels B&Q sell, better to stick with what you've got. There's usually a lot of debris in the heavyweight arenas so softer rubber probably wouldn't be advantageous (might even get dust stuck to it..) but for the Robochallenge arena maybe worth trying a softer compound banebots (http://www.technobotsonline.com/banebot ... re-40.html or even http://www.technobotsonline.com/banebot ... re-30.html) for increased grip.