Indeed they are Joey, they absord impact quite well! Oddly it seems better to have exposed tyres than not to!

Hmm, seems like an all-lego 'bot should be a catorgary of its own. Though I can vouch for these motors, they are good, powerful for their size and the speed of the Xl's isn't bad either. And as for the control, lego now have a speed controller...control thingy bob. So you have complete control over how fast the motors turn.