A quick word of caution.

Yes you can move the SidneyG2 and SimonG2 data files into P6 but DO NOT transfer anything else. Look in the readme. If you install the Poser 7 update files into Poser 6 it will stop working.

Also there is a refinement added to the Poser 7 version to accommodate the G2 waist groups that you'll not get in Poser 6.

Other than that the nuts and bolts of how the program works will be the same in either version.