http://www.army-technology.com/projects/mrav/ The Boxer MRAV uses 'Mission modules, which fit into the base vehicle, provide static battlefield installations to suit the nation specific requirements, including headquarters, medical units and logistic centres. The modules incorporate a primary safety cell with a triple floor. The base vehicle operates independently from the modules. The units are air transportable. The modules are interchangeable in less than one hour.' Has this use of mission modules been tried before and are there penalties in this system?