The most recent model might be the GN-U DOU Model of Goshogun, based on a 'basic' model set for the body and lims and only the head and plates are attached to create a different model each time.
Another one of the most recent models released is the one in the Brave Gokin range, a series of high quality cast models in wich the Goshogun model is nr 08
search for 'Brave Gokin 08 - GoShogun'
The most extensive resource on goshogun toys is to be found at Alan Yen's Toybox
...can we come and play Alen?