I have been using ".ply" and ".obj" as the ones that support color export. ".3ds"
doesn't seem to past a certain size file resolution in points plotting.
There was a fellow who had a system of software working:
MathGL3d 4.1 is witten by the recently deceased
but it doesn't work in my version of Mathematica 9.01.
He used a "bump map" set up that was very nice in version 5.0.
As far as I know, no one has updated his software.