Poser 6 for sure, if DAZ Studio isn't enough for you (I still wonder for who it is enough anyway) then no need to buy Poser Artist (Poser 4) at all. Why settle for outdated stuff if you can have the up to date - state of art version of Poser? Imo even the price is a bargain.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk