Got about 7", that's perfect for me.
Size really doesn't matter that much, because the vagina will change in size in order to adapt to the penis. All you'll achieve by having a long penis is hurting the girl when you're fucking her uterus.
http://isohunt.com/download/16336933/penis+documentary
http://isohunt.com/download/9880295/penis+documentary
Two good documentaries about cocks, for those interested.