I also have both, but I have hardly used Carrara at all. Possibly if I really dedicated the time to learning it I would like it much more, but I really feel the lack of the mini-preview that Vue has. Having been used to this feature from Bryce days, not having it is like missing a limb.

Incidentally, this IS a proper Poser question. Poser should be used in conjunction with other software. That's how it was originally designed.