Having only ever made OpenGL applications, I feel a transition to DirectX may be in order
Autodesk's entire product line migrated to a D3D-only rendering pipeline. Why? Because D3D is the superior API.
I know many of Autodesk apps run in Linux, Mac OSX, Windows and iOS--so I'm curious. The only reference I can find is a long reply from an Autodesk Inventor developer [1] from what looks like around 2007 where OpenGL was removed form their Windows-only app (Autodesk Inventor). It sounded like his beef was with the sub-par driver support for the OpenGL spec amongst video cards and not with the API itself (which I appreciate as an issue, but is very different from this discussion about it being a poorer API).
[1] http://forums.autodesk.com/autodesk/attachments/autodesk/78/...