hi guys,
I've done a lot of work on my own models, and I've personally found that (though a little costly) the easiest method is to design the basic model on CAD or some other design program before having it printed in 3D, then applying additional detail with GS, or your chosen material. This provides a nicer base for creating the initial mould, and by doing the detail after 3D printing you can add a lot more fine detail to the original.
War of the Sendros