Just for the record: one Poser Native Unit for the present Poser versions is 8.6 foot. Note that is a decimal point there! The distance is not 8 foot 6 inches but (8*12 + 6/10) = 103.2 inches = 2621.28 mm.

And for those who like to play with the materials room: The P-node returns the xyz co-ordinates in the rgb channels in units of 0.1 inch.