Hello, 

I am not visiting Renderosity often; I am sorry... I just miss time; I am so busy. 
Well. Just a note right now. 

Every scenes need specific AA parameters. For instance lot of details with many plants and tiny materials will need high values for AA. But flat materials, don't need high AA. SO, no rules. 
 
The renders for the demo was done with a large value of pixels for HQ presentation at last  Siggraph. So reducing the size of the frame it is like a new path of AA. 
For instance and clarify, make a very large render with poor AA quality, then resize to lower version, you will be able to get nice AA.

Hope that helps.   

Thanks.

Philippe Bouyer
www.belino.net