There is no pro pack to buy for p5, only for p4. if you want it all and then some, get P5. this is such a major upgrade its incredible. The only thing is that P4/pp plugs into LW and some other apps and the newness of p5 doesn't have that, but give it a little time, the plugins will come along. If not, I'll post an image of Don eating his Poser hat. P4 and P5 should not be used in the same sentence. (Doh! I just did, so slap me).