Couple modeling Qs:

1) I made a pair of glasses, is there a recommended way of having the glasses lens appear as a lens in VR? I don't know what kind of material or shader I should use for them, other than flipping the normals of it so the top/bottom of the lens can be seen through it.

2) Any difference on the rendering end having multiple materials sharing the same texture vs. one texture per material? Aside from download size packing everything you can into a single atlas, not that I think you can do an albedo+normal map together in the same texture with how Unity wants textures explicitly declared.