Using PP 2012's internal scaling system, V4 is 194cm / 6'4".

To measure things in Poser, I use a calibrated prop that is 1x1x1 meters.

You can easily create such a prop by setting Poser to metric units, then move a prop along the y-axis exactly 100 units.

Scale a cube so that it is as big as that 100 unit distance.

Export it and re-import it.

That's your 100 unit (= 100 centimeter or 1 meter) prop.

By scaling or moving it you now can easily measure everything in your virtual Poser universe.