I have another question. My Z3 has the molded (hard) boot, which becomes problematic when we take a trip and need the trunk space. So we end up leaving it at home. Does anyone use the soft boot I see available at Z3 Solutions? It says it has the same four attachment points as the hard boot. I guess I am wondering what prevents the rear of the boot from flopping in the breeze. Can any of you enlighten me?