Recommended free renderer - An old question, maybe a new answer?

 From:  David (BLEND3D)
3136.23 
If cost is a concern and Blender does not suit might I suggest Bryce 5.5 .... It is an older 3D program that is of a different sort but it imports .obj files rather well. The interface is unusual and seemed to attract artists and repel CAD guys. DAZ still sells it as version 6.1 which includes HDRI support but v5.5 was a relatively fast & stable version.

You can get it here: http://www.daz3d.com/i/support/downloads?product=bryce&_m=d
The only caveat is that you must register for a free DAZ account to get the serial number...
BTW: I notice that the manual is still available as well as the v5.5c upgrade, I definitely recommend grabbing these if you plan to use the program.

To show you what you might expect of it I have included a MoI model and the resulting Bryce render.
Hope this helps,
David
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