Win 98SE

Poser Pro Pack 6.7GB
Poser 4 (without Pro Pack) 6.6GB

I have each version on a different partition. The Poser 4 is a mirror image of the pro pack install except for the stuff added or changed by the Pro Pack upgrade. Some things still don't work right in Pro Pack and it hangs and crashes more than Poser 4 does. Setting them up this way means it doesn't matter which one I make a file in, both can find the same models and textures in their own subfolders.