If you are having a big investment of models then you might consider to remain on Poser 11 or bellow. There are several reasons, Python combability loss due the upgrade on Poser 12, this will cause that many packages you own and have Python Extension will no longer work correctly, allot of creators were using these for Materials and Morphs. Allot of these Packages are really great and would be of no use in Poser 12.  So if you are a Proud owner of Surreality Packages all or most of these would not work and this is just one of many Artists creations. also most lululee creations would be affected. No need to build up a list as it is Huuge!

The other thing is is that Poser 12 is still on Pre Release . If you would be a New user that just goes for the latest La Femme Products then it could be considered to go for Poser 12 with the restriction to skip older sold products avoiding in desiderable conflicts.