I go for a pretty face first and foremost. A girl with gorgeous eyes, a cute little nose, a killer smile, great lips, and all that has got my attention. The rest of her could be overweight and I don't mind at all. If she wears glasses, that's bonus points.
If I have to go by your chicken test, I'll choose breasts. But that goes back to my love of curvy, voluptuous women and their breasts. No surprise there.
