Okay, surprised no-one called me out on my comment above ;) I thought Poser11 still had a texture size limit of 4096, seems that was just the background-size limit.

I have been doing some more testing on render speeds too.

It seems to me that if one ignores the new Adaptive Sampling options then render times are, as I suggested above, about on par with Poser 11.

However, the new Adaptive Sampling is really, really great! Even with the default automatic setting of 0.00 threshold, I see big reductions in render times, but I'm finding values as high as 5 percent useful. This feature alone would be a good enough reason for me to upgrade if Poser12 didn't have other issues as detailed elsewhere. (Primarily Poser12 seems incompatible with a dual monitor setup).

Oh, I think the Intel DeNoise works really well too for cleaning up quick renders if you don't mind the minor softness it understandably brings!

So I'm not giving up on Poser12 just yet, if the dual monitor issue gets fixed I can see myself setting scenes/figures up in Poser11 and then rendering in Poser12.