User blog comment:Urbancommando77/Noble Six vs Courier Six/@comment-4098900-20111206001757/@comment-889585-20111206005955

The only one in Mark IV is Jorge-052, and he is in the version that started testing the Energy Shields. The reason the Mark V was replaced by the Mark VI was becayse the Mark VI was slimmer and had automatic biofoam injectors, thus no need for health packs.