Actually, I think the way e-frontier handles the content is better than "simply upgrading".
By adding an external runtime that points to the Poser 6 root folder, you'll have your neatly organized Poser 6 runtime linked to P7, AND you can still run Poser 6 for things that Poser 7 doesn't do well - such as dynamic cloth calculations.
The other way around also works - if you add the Poser 7 runtime as an external runtime to Poser 6, you'll have the Poser 7 figures available in Poser 6.

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

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