sorry, I don't know why I can't attach 2 files in the same message (I'm a new forum user, you know) anyway this reply let me specify another thing about the size of the two images; actually the Carrara one is 3200 x 2400 px  and the Vue one is 2160 x 1440; that's why the different behaviour of the AA filter to perform similar quality.
The model was taken from the web, I don't remember where and it is in .lwo format