Hello Amit,
In answer to your questions:
1. There is nothing specifically for this purpose, but please be more specific about the issues you are trying to solve and perhaps I can make a suggestion.
2. Not really, other model sets offered for download on the internet are for compatibility with various applications.
3. Not really, the different model sets we offer are meant to provide different technical specifications rather than different face looks. The idea is that you can get any face look with any mesh (within limits for lores meshes of course).
4. No, the internal mean face is not meant to represent a final look, but is merely a starting point where different meshes can be put in correspondence so that a final look is created with FaceGen statistics. You can create a custom look by adding a delta morph from the FaceGen corresponding shape of your mesh to the look you are trying to achieve. Again though, I can be more specific if you let me know what issue you are trying to solve.
Best wishes,