A really interesting question.  I started with Vue in mid January this year but had Bryce, Rhino3D and Poser experience from 2001 and 2002.  I am by no means awesome with Vue but found it didn't take long at all to produce what I considered a half-decent image.

Three things I noticed with Vue.  First, it is amazingly intuitive (at least for me) and that made the learning curve much shallower.  Secondly, there is an unusually large volume of really good quality, free training resources around.  I must have watched 40 or 50 Vue tutorial videos in the first 2 weeks after i bought it.  I learnt alot from them.  And, thirdly, the Vue community just seems super helpful and actually wants to assist newcomers.  Questions are answered quickly and thoughtfully on this and other forums and some forum members will go the extra mile, emailing you materials, atmospheres etc and helping you with an image you might be having difficulty with.  A couple of artists in particular have been a huge help to me.