Parasolids and Version 8 solids can co-exist in the same model. However, it is not possible to perform Boolean operations between solids of different kernels. You must convert one solid before attempting the operation. Also, if a model contains Parasolids, the solids need to be converted manually before exporting back to an earlier version of PowerShape that doesn't support Parasolids. However, you can export Parasolids back to PowerShape products using earlier versions of Parasolid.
It is possible to convert version 8 solids in existing models to parasolids, and parasolids to version 8 solids:
To check whether a solid is a Parasolid or Version 8 solid, right-click the solid to display the solid context menu. It shows:
New models use Parasolid, unless you change the default by selecting the Version 8 solids option on the Solids page of the Options dialog.