Tell me something? If you have Vegas and already can easily render out crisp,
excellent MP4 formats, why in the world are you seeking an alternative?
And even so, doing this gonna compress your video even further, thus reducing
its overall quality!
However, Scott recommended a good choice, which is Handbrake, but instead
of using it as a third party video convertor as you are seeking, there is a script available where you can easily frameserve your Vegas render to Handbrake which is a ton better if choosing this route…
Steve Rhoden (Cow Leader)
Film Maker & VFX Artist.
Owner of Filmex Creative Media.
Samples of my Work and Company can be seen here:
https://www.facebook.com/FilmexCreativeMedia