So as not to be confusing some do go down and some go up in size.  Why...... I have no idea.  Do some comparing of the pz3's and vob's and you will see this.
 
And exapmle is Faverals Medusa ship with furled sails.  The pz3 is 787 kb in size and the saved vob is a whopping 70.8 MB in size.  The reason I think is if you check save the textures it gets them from poser and stores them in the vobs.  So it can be either way with how the person saves the vobs. :)

Also its confusing to compare what is happening when some people are using Vue 6 Final and some are using Vue espirit which I would think  has less coding in it and it might work different than the version **estherau is using.  But then again I have no idea what she uses.

 I am sure there is still memory leaks in Vue 6 Final with last update and its been confirmed so I will not get into more discussions when its been confirmed and will wait till maybe one day Vue 6 is working as I think it should.

 I too am having problems with big scenes and I have been using Vue since Version 4.  Vue 5 inf is till more able to handle big scenes than Vue 6 at the moment.   I hope this will change with future updates. :)
**

ïÏøçö