what is faster to render? loading a textured cube from 3ds or
drawing a cube and texturizing it?
Well, if they both use the same number of vertices, normals, textures, etc..it would be the same since they use the same number of resources (if you are drawing them the same way of course). It just ends up drawing vertices anyway...so there's really no difference.
however you have the initial overhead of loading the 3ds.
But bear in mind that this is more extensible. You can't practically manually render a human model.