Poser 7 will give less OOMs. Two reasons: first, it can make use of more than 2 GB since it's compiled with the LARGE_ADDRESS_AWARE switch. Which means that it can use up to 3 GB of address space under WinXP 32 bit (with the /3G switch in boot.ini) or 4 GB under XP 64 bit or Vista 64 bit. Second, it can render in a separate process, which doesn't have a complete user interface that takes up memory.
It has a few nice additional features compared to P6. First, the morph brush - now you can fix pokethru or make custom morphs without magnets in Poser itself. Second, HDRI lighting. Third, much better Python scripting support (though still not good enough - I'm still missing widgets like treeviews, listboxes, multiline edit boxes and so on for the dialog screens). And fourth, switching between runtimes is far easier in P7.

The pen is mightier than the sword. But if you literally want to have some impact, use a typewriter

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