It is interesting to see the next steps being taken by Tesla. Apparently they have "changed the software that raises and lowers the car based on its speed to increase the default ground clearance." [USA Today March 28, 2014].
Tesla will also "install a 'triple underbody shield' made of titanium and aluminum to the underside of all Tesla vehicles to further assuage worried buyers. They'll even retrofit previous models for existing owners." [The Wire, March 28, 2014]