[Nick LaPosta]

That would depend on where your weight is centered at. The ball isnt going to create much rock if any if your weight is centered low and to the front.

Also on the four wheel drive, my team had a four wheel drive in 2010 and we had trouble steering. You want to try to keep your wheels as close together as possible while still being stable. Otherwise you end up dragging the wheels across the floor making it difficult to turn. That was with the standard rubber 6 in" wheels.