Now, Poser 6 won't render this scene at all, regardless of bucket size. 

Looking at the scene I somehow do find that very very hard to believe. I've done way larger scenes with Poser 6 without a problem.

Anyway going back to your comparisment, to me it's pretty much worthless showing some figures, you need to show the rendered results also. Showing images and times gives us a good comparisment. For all I know even though the C5 rendered image may look terrible. It also depends a lot on the settings. It's hard to compare rendered times if you don't give the used setting also.

*If anyone was curious whether Poser's rendering abilities have caught up to C5's? They haven't. 

*To be honest, I do find P6's rendering abilities far beyond the ones of C5. Just looking at your gallery and toonz it seems to me you haven't even tapped into P6's real rendering capacities. While C5's rendering capacities are great, I find them to be a let down when it comes to the final results. I've used them for a while, but when it comes to rendering Poser scenes, I've returned to the Poser 6 for rendering.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk