picture in picture 3d.

Sorry to hijack this thread, although it is related...

I'm looking at achieve a similar effect. I am coding a GUI system which one of the features will be to open a window and to be able to view unitypackages inside, like an in game inventory 3d model loader.

I'm not convinced render to texture would be the best idea as I need to be able to move, rotate and interact with the 3d unitypackage model.

What might be the best route for this?