Tracy Adams (aka Debbie Blaisdale - not quite sure of the spelling) and Ali Moore are two of my faves from yesteryear. It is my understanding that Tracey was very comfortable working with either gender; her knack for hand jobs reveals her her comfort as well, I think.
Rumor from the past is that Tracey Adams much preferred girls, that she only worked with guys because she "had to". So here we get to see her do BOTH ...