It's all a matter of taste. Personally the more obviously fake and highly articulated the better. So, I think Amy has beautiful big, obviously fake tits that scream out, I wanna be fucked.
A very nice list of Stunning Barbie's from Model Mayhem. I think most of these babes meet the basic criteria.
http://www.modelmayhem.com/list.php?list_id=71531
WOW!! You definitely found the most perfect and ultimate Barbie!! Damn, she's hot and so unlifelike. Too perfect to be real, but I'm sure she is and all.