For the most part I find V4 a huge improvement on V3, and with time (and products) she will probably be amazing.  I picked up the Pro Pack and I'm loving some of the new features.

As of now, though, she is not a replacement for V3.  She does not have the same flexibility.  V3 has her eyes mapped separately, for example, if you want to make one eye blue and one orange, it is really not a big deal with V3.  V4 has her Left and Right eye maps in one material zone.  You literally have to go in a and paint the texture map to get the same effect!

No Alien Head morphs, no oddbal character morphs (ie: gargoyle, hag, etc..)  I never used those morphs out of the box, but I have plenty of V3 renders that you may never know it, but a .085 of some weird character is in there. 

No phenomes!?  WTF?  I'm sorry, but I have free characters from Daz that came with Phenomes.  This is a huge disappointment.  The only reason I got into using Poser characters is for animation.  This should not be in an add on pack, this should have been part of the Pro Pack and the very least, but moreso, it should have been part of the Base figure.  Just a huge disappointment.

Anyone who is having trouble finding some of the features, though (like the grasp hands and such) make certain you didn't download both the Base and one of the full packages.  There is a file name that is apparently the same, and the obj is the same, but the cr2 is different.  I understand this can cause some trouble.

The expressions are amazing, but too few and by this time next year it is going to be really easy to play, "guess the expression morph" in the galleries.  A shame.

Well, I'm off to play some more....