>>8747138They are a first party conversion kit, designed by the garage kit artist muscuto. They are also the most extensive first party megami device original redesign. The other kits are typically new hair and chest plates, where as launcher and lancer got entirely "new" lower torsos, and have a fantasy theme rather than the future knight theme they had before.
A m.s.g. weapon set would not even be remotely close to what the resin kits accomplish.