A couple of slightly better images.
The family of vehicles was initially developed at ROF Leeds at the time the ROF's were being sold off / privatised. As I understand it they were intended to be a 'cheap' system which could be used to develop an in-country capability if required, so were not necessarily cutting edge in terms of performance, but had a degree of modularity incorporated into the design to enable alternative equipment fits to be used.
Some elements continued to be worked on post privatisation i.e. the 120mm AMS mortar system, as the core design was retained within the ROF's when Leeds was sold off to Vickers.