You should be able to use Carrara 5 Pro with Poser content via the Transposer utility that is bundled with the Pro version.

See the following link for information/confirmation
http://www.daz3d.com/i.x/shop/itemdetails/-/?item=4247

I'll be picking up my copy of 3D World over the weekend and I'll report back if there are any limitations or restrictions (but it's said to be the full version).