I started a thread at the BlenderArtists forum, with two renderings of my second Robot bust design, done with two different renderers: Cycles and Luxrender.

http://blenderartists.org/forum/showthread.php?353089-Quiz-which-one-is-the-Cycles-rendering-and-which-one-is-the-Luxrender-rendering

Which rendering do you think is done using Luxrender, and which one using Cycles? And which one is your favorite?

Thanks.