Either curious labs or e-frontier (I dont remember which) had Poser native units as having changed slightly when Poser 6 was introduced. The difference was minor

ONE POSER NATIVE UNIT IS THE EQUIVALENT OF 8.6 FEET, OR 262.128 CENTIMETERS from the Poser 7 manual , thats 103.2"  

I use a conversion factor that a friend had developed and while not accurate it is close enough for modelling in real world units .