[slent thndr]

With the system you describe it seems that the robot is never driving in a direction which is perpendicular to one of the wheels, so why are the omni-directional wheels necessary? Unless you were traveling straight in a diagonal I guess... in that case would two of the wheels be turned off? For instance, if traveling diagonally forward and left, wouldn't front left and back right be off, and front right and back left be traveling forward?