Carrara6 has a better dynamic hair to Poser, faster render, better light handeling, particles, flame, ect.ect. my avitar was the first thing I did when I got C5pro, C6Pro is better.

Carrara does not have dynamic cloth, promised but that's a Daz promise so who knows what year that will be. Can't rig for use in Poser, DS, not sure if anything can use Carrara rigging. But. there is no rigging in Vue. It uses Poser to pose and use the Poser shaders. A few bugs but that's normal. Posing is slow and a pain compaired to Poser.

DS has gotten up there in price now. Not sure but it might be about the same price to get Carrara as it is to buy all the DS plugs, if not it's got to be close.

Try the demos of Carrara, Vue and anything else first. See what your needs are first.

I use Carrara6Pro, Vue6I with Poser 7. They all do something the other doesn't. I also use Hexagon2.1 and Modo301 for modeling. Carrara's modeling tools and room kind of sucks.