After the completion of the Future of Us Launch Video, I took some time to test Nvidia's iRay renderer.
iRay is included in 3D Studio Max 2015. However it is not included with Maya. I found that the company 0x1 has implemented an iRay for Maya plugin, sold as a commercial product.
Using the car model from the previous project, (which was purchased and modified), I set-up iRay shaders for it.
The background image is being used as a source for image based lighting and reflections.
The depth of field and motion blur are in-render, rendered as a single pass. Each frame took 12 minutes (cpu/gpu batch render) on a dual Intel Xeon 2.5ghz with 64gb system RAM, and an nVidia Quadro M600. (This is the machine I'm using at work).
iRay for Maya is responsive. I really love the interactivity. I have not tried rendering in passes and compositing images with it, but from the video links for their product site, it seems quite possible to achieve a passes-based workflow like all other renderers.
iRay for Maya is available as a 30 day trial from 0x1 Software and Consulting.