In our Windchill system we use the Product (and Library) as 'CAD Archive, so we don't want it 'polluted'.
The Project is used to try concepts, as playaround area.
In this context, enabling in the Project to use SaveAs for shared objects (to new objects in the project) is a must.
Save As should also work for shared objects.
checking out an object first makes no sense, because it would require a Revise in the Product while that CAD data is not in change (you just want to make a copy to try something or to start a new product quickly ...