Think you have to be very careful judging a render based on a very few settings. I dont know vue or carrara render very well. And im not a lighting expert my self in anyway. But as a comparison mental ray (3ds max in my case) without any tweaked settings wont create very nice renders either, and im not even sure a raw mental ray render would render as good as any of those images you have posted, and if the settings are "wrong" they will be even worse. However it is very capable of doing realistic renders if you know some about lighting and what the settings should be.
But setting up light, at least in my opinion is really difficult if you aint to sure what all the light and render setting are suppose to be, and maybe know some theory behind how light works.  Especially if you want to set realistic lighting.

But its a fun test non the less, and it could be fun to get some light guru to check it out :)