Real-Time Rendering in Maya Viewport2 - X-Ray
X-Ray is made to be more artistic than physical accurate, you can control lights and reflection, unlike any other rendering tool, as you can see in this video after you captured the scene reflection for your mesh you can open it up in photoshop and make any changes and it will update on your model.
X-Ray is made to use the power of other render engines to its advantage giving you the ability to get the best out of each render engine and see all of it in real-time right in viewport. the next update adds support for Redshift! the lights in this scene are simulated using Redshift and the reflections are captured with Turtle. using redshift as your lighting core you can also control GI separately which gives you an additional level of control.
X-ray is available as a bundle with MayaX.
https://cgelementary.gumroad.com/l/MayaX