Howdy,
here are two sample images of a work in progress to showcase Biosonic systems (http://biosonic.divatech.fr/Offre_Mach3.htm).
Before:

After:

Each image rendered in 1h30 at this size (Dual Xeon 3.2Ghz), with aQMC AA at 1x4 and Sinc filter.
A lot of blurry reflections and bump, so I’m pretty happy with the speed so far.
The GIs are very predictible, as the solutions don’t change much between frames.
I used irradiance map at min/max -4/-2, with enhanced details On, and light cache with 1000 samples.
There’s a portal in the window, which send GI shadows with 32 samples.
For exposure control, betweem color mapping, GI rays intensity and Vray camera controls, there’s a lot of tool to make getting the correct exposure a breeze. Of course, it doesn’t replace the artist’s eye but gives him the means to achieve what he wants.
I’ll update later probably, as the client asked for some changes.
P.S: Regarding the Vray material converter, everybody should keep in mind that c4d materials are not supported directly (I’m talking about the material, not the c4d shaders) and need to be converted to Vray materials. It’s of course a no-hassle one click thing, and most materials setups translate seamlessly.
Very good job from Renato and Daniele here!