Is there a way to change the default materials an item or character initially loads with?

in New Users
For example, I'd like to load an item to the scene that has Iray materials by default, but I want to use the 3Delight materials instead without having to always switch/add the appropriate shaders/materials every time I use it. Is it possible to change/save these settings as the new default?
If it's possible, it may convince me to buy more items or pick up some new freebies, since I also use the conversion script mentioned in this forum post.
If it is different the opposite way (3Delight to Iray) I'd like to know too for future references or whenever I upgrade my PC.
Comments
Just save a new Character preset with the desired materials, or a Scene subset (both in the File>Save as menu).