There is mGear for Maya and Rigify for Blender! Me as a self-taught rigger always prefer to learn how to build a custom rig from scratch and then develop a tool to implement it. However lately I have been trying out these autorigger tools and I would say if you are already familier with the concept of rigging and comfortable with it then feel free to use these tools to assist in production. I don’t however recommend these tools to beginners who are getting started with rigging and want to make a career out of it. Take your time to learn the basics, build your own custom rigs and then learn from these tools 🙂