I am thrilled with POser 5. The hair room and material room are great. Features like reflections and ray tracing are included as are boning and displacement maps. It really is miles more advanced than Poser 4. Everything in Poser 4 is included in Poser5 - all the people like Posette and the animals. There are also the Poser 5 people (Judy & Don) who can use the amazing face room and some cute cartoon characters. If you want Poser Pro Pack you need to buy Poser 4 as well - it is an add on not a stand alone.