>  I think VW made the bumpers soft
>  to take the damage, in order to protect the rest of the vehicle.

That could be the case.  I have seen many instances where a rear Vanagon
bumper was creamed and the body unscathed. (Then again, a 1-mph collision
would cream that bumper :-)   A bumper that did not "give" when hit could
possibly cause the bumper mounts to be pushed forward into the frame, rather
then the bumper simply bending instead. While probably not dangerous, this
could potentially cause more damage than the cost of replacing a $150
bumper.  I suspect there is a middle grounds between a stronger-than-stock
bumper that can withstand at least some impact, and a too-rigid one that
might withstand the impact a little "too well."

- Ron Salmon
 The Bus Depot
 http://www.busdepot.com